Tustna is an island in Aure Municipality in Møre og Romsdal county, Norway.

The Edøyfjorden runs along the northern shores of the island, the Vinjefjorden (and Halsafjorden) are to the south, the Freifjorden is to the southwest, the Talgsjøen is to the west, and the open Norwegian Sea is to the northwest.

There is another ferry connection from the northern coast of Tustna to the island of Edøya in Smøla Municipality.

[1] The Old Norse form of the name in unknown (the name of the island is first mentioned on a Dutch map from 1623: Toester).

It might be derived from the word þústr, which means 'staff' or 'stick', and in that case it is probably referring to the form of one of the mountains on the island.