The sole prototype G1M, initially designated Mitsubishi Navy Experimental 8-Shi Special Reconnaissance Aircraft and re-designated Mitsubishi Navy Experimental 8-Shi Land based Medium Attack Aircraft before first flight, was a predecessor of the Mitsubishi G3M, an important step for the Navy air force towards more capable land-based bombers such as the Mitsubishi G4M "Betty".
There is sometimes confusion between this aircraft and the Mitsubishi 3MT5 (also designated 'Mitsubishi G1M' and 'Navy Experimental 7-shi Carrier Attack Bomber'). The 3MT5 was a biplane, and the 8-shi experimental Attack Bomber was a monoplane, two entirely different aircraft.