The Catalina affair (Swedish: Catalinaaffären) was a military confrontation and Cold War-era diplomatic crisis in June 1952, in which Soviet Air Force fighter jets shot down two Swedish aircraft over international waters in the Baltic Sea.

The first aircraft to be shot down was an unarmed Swedish Air Force Tp 79, a derivative of the Douglas DC-3, carrying out radio and radar signals intelligence-gathering for the National Defence Radio Establishment (Försvarets radioanstalt, FRA). None of the crew of eight survived.

The second aircraft to be shot down was a Swedish Air Force Tp 47, a Catalina flying boat, involved in the search and rescue operation for the missing DC-3. The Catalina's crew of five were saved.

The Soviet Union publicly denied involvement until its dissolution in 1991. Both aircraft were located in 2003, and the DC-3 was salvaged.