An electric toy gun includes a gun body carrying a piston set and a gear set having a first gearwheel provided with a side pin and rotatable to move the piston of the piston set, and an attached cartridge carrier, which includes a propelling member movable back and forth by the pin of the first gearwheel, a swivel hook member turnable back and forth by the propelling member, a cartridge rack hung on the swivel hook member and movable back and forth with the swivel hook member to simulate the cartridge feeding operation of a real gun and a return spring for returning the propelling member.