[3] Oyashio, built at the Maizuru Naval Arsenal, was laid down on 29 March 1938, launched on 29 November 1938 and commissioned on 20 August 1940.

[4] At the time of the attack on Pearl Harbor, Oyashio, was assigned to Destroyer Division 15 (Desdiv 15), and a member of Destroyer Squadron 2 (Desron 2) of the IJN 2nd Fleet, and had deployed from Palau, as part of the escort for the aircraft carrier Ryūjō in the invasion of the southern Philippines and minelayer Itsukushima.

On 5 March Oyashio and the destroyer Kuroshio located an unidentified British ship which they believed to be a minelayer and engaged the enemy.

In early June, Oyashio deployed from Saipan as part of the troopship escort for the Battle of Midway.

Upon learning of the action at the 2nd battle, Oyashio departed alongside the destroyer Kagerō to engage the enemy ships.

They joined the fight late, but managed to fire a torpedo spread against the American battleship USS Washington, but inflicted no damage.

On the 29th, Oyashio departed for a supply transport mission, but the next night was intercepted by a US cruiser-destroyer force in what became known as the battle of Tassafaronga.