Ha-108 was an Imperial Japanese Navy Ha-101-class submarine. Designed as a transport submarine, she was completed and commissioned in May 1945 as a submarine tender for midget submarines. She served during the final months of World War II, surrendered at the end of the war in September 1945, and was scuttled in April 1946.
The Ha-101-class submarines were designed as small, cheap transport submarines to resupply isolated island garrisons. They displaced surfaced and submerged. The submarines were long, had a beam of and a draft of . They were designed to carry of cargo.
For surface running, the boats were powered by a single diesel engine that drove one propeller shaft. When submerged the propeller was driven by a electric motor. They could reach on the surface and underwater. On the surface, the Ha-101s had a range of at ; submerged, they had a range of at .
The boats were armed a single mount for a Type 96 anti-aircraft gun.
Ha-108 was laid down on 5 September 1944 by Kawasaki at Senshu, Japan, as Small Supply Submarine No. 4608. She was launched on 28 December 1944 and was named Ha-108 that day. She subsequently was towed to Kawasakiâ²s shipyard at Kobe, Japan, for fitting-out. Prior to completion, she was converted from a transport submarine to a submarine tender for midget submarines, the conversion involving the reconstruction of her cargo hold to allow her to carry ten torpedoes for midget submarines and a tripod hoist aft so that she could handle them. Her fitting-out and conversion were completed on 6 May 1945, and she was commissioned at Kobe that day.
Upon commissioning, Ha-108 was assigned to Submarine Division 33 in the Kure Submarine Squadron for workups. Hostilities between Japan and the Allies ended on 15 August 1945, and on 2 September 1945, Ha-108 surrendered to the Allies at Maizuru, Japan. On 2 November 1945, she was reassigned to Japanese Submarine Division Two under United States Navy command along with her sister ships , , , , , and . In November 1945, the U.S. Navy ordered Ha-108 to move to Sasebo, Japan.
The Japanese struck Ha-108 from the Navy list on 30 November 1945. She was among a number of Japanese submarines the U.S. Navy scuttled off the Goto Islands near Sasebo in Operation Road's End on 1 April 1946, sinking just beyond the line at .