The Aleutian Tern (Onychoprion aleuticus, formerly Sterna aleutica - see Bridge et al., 2005) is a seabird of the tern family Sternidae.

This species breeds in colonies on coasts and islands in Alaska and easternmost Siberia. It is strongly migratory, wintering off Indonesia and Malaysia. Large numbers appear off China during passage periods.

It is a very rare vagrant to western Europe, with just one record, on the Farne Islands off Northumberland, England on 28-29 May 1979.

It lays 2-3 eggs in a ground scrape. It sometimes nests among Arctic Terns, which, like most white terns, are fiercely defensive of their nest and young and will attack large predators.

Like most other terns, the Aleutian Tern feeds by plunge-diving for fish, usually from saline environments. The offering of fish by the male to the female is part of the courtship display.

This is a medium-sized tern, with a short, pointed bill and a long, deeply forked tail. It has a black cap with a white forehead, dark gray mantle and underparts and a mostly pale underwing with a dark secondary bar. It has a white rump and tail, black legs and a black bill.

The call is a musical whee-hee-hee.