HMS H34 was a British H class submarine built by Cammell Laird, Birkenhead. The vessel was laid down on 20 November 1917 and was commissioned on 10 September 1919. She had a complement of twenty-two crew members. HMS H34 was one of the seven H class submarines to survive until the end of World War II. During Warship Week 1942 H34 was adopted by West Dean RDC (Gloucestershire). She was sold for scrapping in Troon in July 1945.