A ratchet screwdriver includes a mounting seat, a fixing ring, a control member, a driving shaft, two pawls, two springs, a fixing ring, a control member, a bead, a positioning spring and a bolt. The mounting seat has a front with a first slot, a second slot, a first extension slot, a second extension slot, a passage, a first hole and a second hole. The driving shaft has a ratchet portion. Each pawl is biased by one spring so as to be engaged with the ratchet portion. The control member is rotatably mounted to the mounting seat and the driving shaft to pivot the pawls to engage or disengage with the ratchet portion.