Usui is a Japanese term for yushui, one of 24 solar terms.

Usui may also refer to:

Usui (surname), Japanese surname Usui Bridge, brick masonry bridge in Gunma prefecture, Japan Usui Pass, mountain pass between Gunma and Nagano prefectures, Japan Usui District, Gunma, former district in Gunma prefecture, Japan Usui, Fukuoka, former town in Fukuoka prefecture, Japan (now merged into the city of Kama) Usui Kojima (1873–1948), Japanese author