The Ki-30s were first used in combat in Second Sino-Japanese War from spring 1938. It proved to be reliable in rough field operations, and highly effective while operating with fighter escort. This success continued in the early stages of the Pacific War, and the Ki-30s participated extensively in operations in the Philippines. However, once unescorted Ki-30s met Alliedfighters, losses mounted rapidly and the type was soon withdrawn to second-line duties. By the end of 1942, most Ki-30s were relegated to a training role. Many aircraft were expended in kamikaze attacks towards the end of the war.
From late 1940, the Ki-30 was in service with the Royal Thai Air Force, and saw combat in January 1941 against the French in French Indochina in the French-Thai War. 24 aircraft were delivered, and were nicknamed Nagoya by the crews. Additional Ki-30s were transferred from Japan in 1942.