Umihara Kawase (海腹川背^?) is a series of platform games, starring a nineteen-year-old Japanese school girl, Kawase Umihara (海腹 川背 Umihara Kawase), who has somehow become lost in a world of mutated salt-water and fresh-water creatures. She wears her school uniform along with a bright pink rucksack. The Umihara Kawase games' main distinction is their tranquil fish and bird infested worlds and the rope physics, which defines the gameplay.

The name is written as four kanji characters: umi, hara, kawa, se meaning sea, belly, river, back. This is an extraction from a Japanese kitchen idiom "Sea fish are fat in the belly; river fish are fat in the back." Shun means "in season".

The protagonist was first seen in the eponymous Super Famicom release of 1994 and later the sequel and re-release of Umihara Kawase Shun (海腹川背・旬 Umihara Kawase Shun) for the PlayStation in 1997 and 2000.