Founded in 1971, a 5-minute walk from Sakata Station. Selected as Tabelog Sushi EAST 100 Best Restaurants 2025 (score 3.72, 418 reviews) — the undisputed top sushi restaurant in Yamagata Prefecture. Serves rare Sea of Japan fish including nodoguro (blackthroat seaperch) and gasa shrimp, all caught from Shonai coast and prepared with Edomae technique. The 10-piece seasonal local omakase nigiri at 3,000 yen offers extraordinary value. So accomplished that sushi lovers from other prefectures became regulars through word-of-mouth. One of the few sushi-kappo restaurants also open for lunch.

Reviews say: 'Always stop at Koise when visiting Yamagata,' '3,000 yen for this quality is unbelievable,' 'The nodoguro is three times better than anywhere else,' 'The best place to understand Sakata's local fish.' Tabelog 100 Best 2025 selection proves it. Many out-of-prefecture regulars — not a tourist trap but a genuine gem where sushi lovers find it by word-of-mouth.