A combustion-type power tool includes a cylinder, a piston, a head, a combustion chamber frame, an ignition unit, a trigger, a control member. The combustion chamber frame is abuttable on the head to provide a combustion chamber in cooperation with the head and the piston. The trigger is operated by a user for driving the fastener into a workpiece. The control member detects that the combustion chamber has been provided and the trigger has been operated, and allows the ignition unit to ignite the combustible gas only when the control member detects that both the combustion chamber has been provided and the trigger has been operated.