The 25th Air Flotilla (第二五航空戦隊,, Dai Nijūgo Kōkū Sentai, "Nijūgo Kōsen") was a combat aviation unit of the Imperial Japanese Navy Air Service (IJNAS) during the Pacific Campaign of World War II.

The 4th flew bombers, the Tainan fighters, and the Yokohama reconnaissance aircraft.

The flotilla, under the command of Rear Admiral Sadayoshi Yamada, was deployed to Rabaul, New Britain on 29 March 1942.

From this location, the unit supported Japanese military operations in the New Guinea and Solomon Islands Campaigns.

The operational title for this hybrid organization was the 5th Air Attack Force.