The 2nd Fleet (第二艦隊, Dai-ni Kantai) was a fleet of the Imperial Japanese Navy (IJN) created as a mobile strike force in response to hostilities with Russia, and saw action in every IJN military operation until the end of World War II.

Established on 27 October 1903, the 2nd Fleet was created by the Imperial General Headquarters as a mobile strike force of cruisers and destroyers to pursue the Imperial Russian Navy's Vladivostok-based cruiser squadron while the remaining bulk of the Japanese fleet (the IJN 1st Fleet) continued to blockade Port Arthur in hopes of luring the battleships of the Russian Pacific Fleet into an open sea classic line of battle confrontation.

As the main mobile force in the IJN, the 2nd Fleet saw the bulk of all future IJN combat operations from the time of its inception until IJN dissolution at the end of World War II.

Based at Samah, Hainan Island[1] 4th Division 5th Division 7th Division 8th Division Other 2nd Destroyer Squadron 4th Destroyer Squadron