Kõinastu is a 2.62 km² islet in the southern part of the Väinameri Sea, Estonia.

[2] Administratively, it forms Kõinastu village which is part of Saaremaa Parish, Saare County.

Kõinastu has a population of 4, as of 1 January 2011[update].

[1] There is a light beacon on Kõinastu.

This Saare County location article is a stub.