Thoressa varia is a butterfly of the family Hesperiidae.

It is found on the islands of eastern Asia, including the Sakhalin Islands and Kuril Islands, Japan, the Korean Peninsula and north-eastern China.

Its Japanese common name kochabane-seseri can be translated as "small brown wing" (ko means "small" and chabane means "brown wings").

Adults are on wing each year from June to July.

The larvae feed on Sasa kurilensis.