MS 15 launched on 2 February 1942, finalised on 2 June 1942, entered service after construction in the Regia Marina's 1st Squadron, and arrived at operational bases in North Africa in July 1942; the following month it carried out, with MS 11, a mission to transport saboteurs of the San Marco Regiment in enemy waters, participated in anti-ship ambush operations, escorting coastal convoys and anti-submarine surveillance.
In January 1943, he carried out a period of work in Monfalcone, returning to the Dodecanese; when the Armistice of 8 September 1943 took place, he was on Rhodes and was part of the Co-Belligerent forces; later the island was captured by the Germans, on the 11th, the MS 15 was transferred to Leros where she took up the defence against the Germans; on 25 October 1943, the MS 15 was at berth in the port of Leros, she was hit by bombs during a German air attack, the MS 15 was set ablaze and sank soon after due to the explosion of the petrol depots
MS 15 was only to be struck off the official documents of the Italian Navy on 18 October 1946.
