The 5th Fleet was initially formed on 1 February 1938 as part of the Japanese military emergency expansion program in the aftermath of the North China Incident of 1937.

The initial plan was to construct 3rd, 4th and 5th China Area Fleets to cover the invasions of Japanese troops into the Chinese mainland, and to interdict and control commerce on the coasts.

[1] With the outbreak of World War II, and the Doolittle raid on Tokyo, the 5th Fleet was reinforced by a large number of converted armed merchant vessels.

The cruisers of the 5th Fleet – designated the "Northern Area Force" after its augmentation for the operation[2] – covered the landings of Japanese troops on Attu and Kiska on 6–7 June 1942, and were in the Battle of the Komandorski Islands against the United States Navy on 27 March 1943.

It participated in the Battle of Leyte Gulf, and surviving vessels were joined to the Southwest Area Fleet on 15 December 1944.