Ostrya is a genus of eight to 10 small deciduous trees belonging to the birch family Betulaceae.

The genus is native in southern Europe, southwest and eastern Asia, and North and Central America.

The genus name Ostrya is derived from the Greek word ὀστρύα (ostrúa), which may be related to ὄστρακον (óstrakon) "shell (of an animal)".

][citation needed], this hard and stable wood was historically used to fashion plane soles.

Ostrya has the following species:[1][4] †Ostrya scholzii fossil seeds of the Chattian stage, Oligocene, are known from the Oberleichtersbach Formation in the Rhön Mountains, central Germany.