Went to the Mediterranean in December 1939 together with the four Australian V-class destroyer to form the 19th Destroyer Division for service with the Mediterranean fleet. In July 1940 HMAS Stuart was present at the Battle of Calabria and on 17 August 1940 she took part in the operation of bombarding Italian troop concentrations near Bardia, Lybia. During the night of 19/30 September 1940 HMAS Stuart attacked the Italian submarine Gondar with depth charges. The submarine was forced to surface the next morning and scuttled by her crew. In January 1941 HMAS Stuart supported the capture of Tobruk. In March 1941 she was present at the famous Battle of Matapan. In April she escorted troop-convoys to Greece and the following month she participated in the evacuation from Greece and Crete. In June she took part in convoy operations to the beleaguered city of Tobruk. HMAS Stuart left the Mediterranean for Fremantle on 22 August 1941. The ship was badly in need for a refit, she had sailed home on one engine, and was under refit at Melbourne until April 1942.

From April 1942 untill October 1942 she escorted coastal convoys and from October 1942 untill March 1942 she escorted convoys from Australia to New Guinea. For the remainder of 1943 and 1944 she again escorted coastal convoys in her Home waters.

During March and April 1945 she was converted to a store and troop carrying vessel and served in this role of New Guinea.

Stuart was decomissioned at Sydney on 27 April 1946 and on 3 February 1947 she was sold to T. Carr and Co.,Ltd. of Sydney to be broken up for scrap.