Sushi Koyo

After coming to Sushi Koyo for THIRTY years Hiro has retired. We will miss this little place!

POSTING this review (I had this draft sitting around for too long) as a note of appreciation to Chef Hiro and his staff for running one of the best restaurant Diamond Bar ever had:
Sushi Koyo is as hidden as a place can be in Diamond Bar or anywhere else for that matter. Located next to a H&R Block and what can be described as a more than dead shopping plaza, Sushi Koyo only has a small door and a neon OPEN sign that alerts potential customers to its existence.
In that sense, Sushi Koyo is definitely kept «secret’ of the area and definitely the best sushi place you can find not just in Diamond Bar, but anywhere within a 20 mile radius.
Although not as cheap as your «standard’ sushi restaurant (this restaurant does serve real sushi btw, not your fried rolls crap or philly roll type stuff), nothing is really that expensive either — expect to shell out a 4 – 6 bucks for two pieces of sushi, which can add up fairly quickly if you’re looking to fill yourself.
You have choices that range from going through omakase style, choosing individual sushi, or indulging in weekly specials that have are usually customized for two people to share and usually cost around $ 40-​$ 60. The fish on the sushi is fresh and usually served on rice that is moist and warm. I love the salmon roll and the blue crab roll is delicious as well.
Although small and humble, Sushi Koyo packs a big punch for those who love sushi. I definitely recommend it as the only sushi place anyone in either in Diamond Bar or any neighboring city should visit and it is well worth the money.

Hiro served his last omakase on August 28^th. He and Utako are enjoying their retirement.
We will miss you sir.

Expensive… uptight attitude… this place should be called sushi nazi…(like seinfield’s soup nazi) gives you what he wants, charges what he wants… not a good experience. Taste fair… nothing spectacular.
Ambiance below average… you can hear your own steps… nahhh won’t be back…
2 people $ 100 for average sushi.

Sat for half an hour waiting for our sushi then left because it took way too long. Bad service. Wouldn’t recommend dining here unless you have a solid 2 hours to spare for your dinner.

I’m glad that my family and I finally got around to trying out this place. We’ve been having a hard time finding a good traditional Japanese sushi restaurant. Our neighborhood has been flooded with fusion sushi. While ok, that’s not the style that we’re looking for when we go out to eat sushi. We’ve finally found it here, but we were also quick to learn that the owner/​sushi chef will be retiring at the end of August after being open for 32 years. They’re a Mom and Pop operation very similar to another traditional Japanese sushi restaurant in the city where I grew up.
*Omakase*
Chef’s choice. The way he does it here is basically he keeps making sushi that he thinks you’d like to eat until you’re full. So the amount you pay is dependent on how much and what you eat. If you decide to sit at the sushi bar, this is your only option. Sitting at the bar is the best for omakase since you can let him know what kind of fish or seafood that you prefer. All of the items that he served us was fresh and delicious.
*Special Sushi lunch for two*
My mom and younger brother shared this special. Along with the plate of sushi and a couple of hand rolls, it came with miso soup. My mom doesn’t eat much and she said that the portion was too small for two people to share.
Overall, if you want fusion rolls drenched in various sauces, look elsewhere. If you’re looking for traditional Japanese sushi give this place a try before he retires!

If you haven’t tried it, you’ve got one month to try it. After 32 years of business, Sushi Koyo, probably the best traditional sushi place in SoCal, will be closing at the end of August ’15. It’s not cheap, for sure, but it doesn’t taste cheap either. It’s worth stopping by for sure!

While most sushi bar closes on Monday, this location opens every Monday! This place is located in a hidden retail center on a quiet street in a residential area. It’s a bit hard to find because it’s tucked at the back of the plaza and it’s a small location that holds about 30 ppl.
The sushi was fresh and the prices were reasonable. I ordered the tekka don which was a bowl of sushi rice served over thick slices of tuna. The bowl was delicious and fills you up well for only $ 12. I was impressed with the sushi rice too. My co worker order the chirashi bowl and he said it was delicious too. They had a good mixture of dish and the fish portion was a decent slice. The handrolls they make are so good portion with lots of fish! My fav was the blue crab and tuna rolls.
The service was friendly and attentive. They do also check in from time to time. I like that even thought this place

Definitely a hidden gem! The restaurant is way on the plaza corner hard to find, with no too much sign also.
I notice this restaurant on Unilocal for a while. Decide to visit for my birthday. There are no customer at all on Saturday dinner time around 7pm. I was hesitate wether the ratings were reliable. But once I had a bit of their food, I was cheer that it is a 5 star restaurant. Server is an old Japanese lady. She s really friendly.
Food 5 star. Service 5 star. A little pricy but food worth every penny! Will come back! !

If you want better sushi, go to Japan!

Location:
After reading so many good reviews about this place, I thought I would give it a try simply because its CLOSE! Theres only a few good sushi places around here, so sometimes you just want to try something new! Hahah! If it wasn’t for Unilocal… no one would every find this place.
Customer Service:
It was almost non-​existent, if anything they were really rude!
Firstly, we were the only customer at the time when we arrived it was about 1hr before closing. We asked if we can both sit at the bar, since only one of us was getting the omakase and I didnt want to, since I wasn’t very hungry due to having a late lunch that day lol. I know I read the sign «ONLY OMAKASE CAN SIT AT THE BAR.» We were like can u made an exception, since they were closing up soon! He told us NO! I really don’t see why he couldn’t just bend the rules –_​_​_​– THEY NEED NEW MANAGEMENT! So we had no choice but to sit at the tables.
Secondly, when we were asking the server for the drinks menu, which is a older gentlemen lol he looked super lost like the words that were coming out our mouth was something new to him? So we were like just water and he went and got us some. After looking around we saw that they had beer and sake. So we asked again he was like «oh, I thought you said something else and yes we have it»…LOL are you serious?
OMG words cannot describe how I felt when they basically hurried us out of the door :(
Food:
It was pretty good and sorta mediocre at the same time, but definitely not going to come back due to customer service. The only thing that stood out to me was the blue crab hand roll and their pink scallops! If I remember correctly their uni was actually pretty good that day, it was very creamy and had good color. I think he also gave us salmon and tuna which was ehhh. One of the white fish was good.
Price:
If I remember correctly its about $ 65 ish for the omakase that my friend had, but I dont think it was that worth it. Sake was reasonably priced.
Conclusion:
Probably will not come back ever lol.

Delicious and authentic sushi. Somewhere I can take my Japanese parents and get a positive review!

Descent sushi but not wow.
Had omakase at the bar. Over all, bit above average. As for service? Pretty slow. The chef? The word «sushi nazi» comes to mind. It would be better If he tried less bragging about him self and put that effort in to food.
The price, tad high for the service and food you get.
I love the fact that this is not a place that caved in to rolls and bowls for sake of more business. Real sushi. This fact may have me comeback for another shot.

Anyone who eats quality sushi knows this place is a hidden gem. Love it. Love Hiro. And his loyal patrons will always come back.
Fresh sashimi lunch for only $ 10.95 and a chirashi bowl for only $ 12.95??? YES! Not to mention this is the BEST blue crab hand roll I have ever had in my life.
My entire family eats sushi and sashimi regularly from cheap AYCE places to Sushi Gen in Little Tokyo to even the highest, priciest places in Japan. This place is amazingly good, with great prices, and a sushi chef who always makes you feel welcome. Will definitely come back!

Things are good here but be warned if you consider spicy tuna rolls sushi or you are looking for rockin roll spider, or anything with mayo and siracha base this is not for you.
Eat the scallops, blue crab hand rolls, and butterfish. The rest leave it up to Hiro to tell you what’s in season.

In very few occasions do I dream about returning to a restaurant before I leave.
Sushi Koyo is a hidden gem tucked inside of a strip mall off of the 57. I know it has been recommended to me before but somehow I never thought that a sushi restaurant that was inland of me could be so impressive that I would gush over it.
The sushi bar is omakase. My meal was mostly onigiri. I had a delightful time and I don’t know exactly what I ate, but I feel like the experience was worth my hour drive and the amount I paid.
I almost don’t want you to come here. I don’t want this place to become like a trendy restaurant where I wait in line. But if you care about sushi. If you have this idea about sushi where it is this guy who puts amazing gems from the ocean in front of you. If you dream about unagi more than burgers. You must make the pilgrimage.

I’ve lived super close to this place for a decade yet I’ve never been. For such a big sushi lover, it’s hard to believe I’ve never seen nor been to this place.
Now, if Unilocal didn’t exist, no one would ever find this place. The location is at the edge of the suburb and beginning of the industrial side. The small sign with such a neutral color to the wall behind it and the incognito entrance that makes this place incredibly easy to miss.
Enough about the location, lets talk food:
I had high hopes coming here because of my fellow Unilocalers raving reviews.
Their menu was great, simple and no BS. None is those teriyaki chicken or beef or anything for people who don’t eat sushi.
I wish I can say the same about their fish.
Uni had the right texture but was way too fishy. Meaning. It’s been dead for too long. Coloring was way off on the uni.
Albacore and yellow tail were decent. A little too fishy as well.
Eel (cooked) was way too fatty it was gross. Either too fatty or too much skin.
Spicy tuna was bleh. You can’t really mess up on it.
The best tasting one was the blue crab hand roll. Taste was there but too much mayo and rice.
Don’t understand how the ratings are so high.

I went there to celebrated my friend b’day on Monday night. This place got good review n close to our house. I was so excited and cant waited to try. We walk in and see only one customer sitting on sushi bar talking to chef. I am surprised how empty this place. Waiter just seat us down table. it seem like the waiter doesn’t understand English that well. The waiter said that he could make for 3 people for Dinner special, since there are 3 of us.
$ 39 Dinner Special for 2 — Which is good deal
Baby Tuna Sashimi
Blue Crab Hand Roll
Spicy Tuna Hand Roll
Salmon
Tuna
Butterfish
Albacore
2 Miso Soup.
Also, ordered on the list
3 Yellowtail
2 Smelt Egg
2 Salmon Egg
Dinner special came out only for 2 person only. When I ask the waiter, we ask for 3. He reply, that he cant do that. He should have told us from beginning. We don’t mind pay extra or order another set. Anyway, we end up order extra soup. Will order more after we finish 1^st round. Boy, I am glad that we did not order that much. Sushi doesn’t look fresh and doesn’t taste fresh. Rice fall apart when pick up after dip into the sauce. Smelt Egg & Salmon Egg are very fishy. My friends said the sushi are very rough texture because bad cut
I left the place like I never eat anything. Still hungry and looking for another place close by to eat. I was disappointed and too pricey. Not worth it for the price. We probably wont go back there again.

Had Omakase and really enjoyed everything. Asked how much it costs before sitting down at the sushi bar and the server told us $ 40 – 50 per person.
Tried many different and excellent plates– then requested the check. Found out it was $ 85 per person. Ouch.
We were the only customers there and it felt like a bait and switch.
Sushi was good– but just be sure that you ask the boss man behind the sushi bar what the price is. I don’t think they were trying to mislead us– I just think the server guy was clueless.

I come here with my dad whenever I’m in Diamond Bar. We sit at the counter and get the omakase, which comes with edamame. Not only is Hiro-​san an amazing sushi chef, he is also hilarious and welcoming.
All of the sushi was good, but what put it over the top was the preparation. I especially loved the big eyes tuna simply for the quality of fish. One of the preparations that I loved the most was the butterfish; I’m craving it as I write this. The sushi with the thin slice of seaweed (maybe cucumber?) was also a preparation that I’ve never had before but was yummy.
Service is always great and everyone is super friendly. Just remember to respect the rules of sushi– no «American» rolls and no bowls of sushi rice with just soy sauce.