Locating and shifting structures of a movable joint of a ratchet screwdriver

A ratchet screwdriver comprises a handle, a main body, and a movable joint member fastened between the handle and the main body. The joint member is formed of a ratchet portion, and a locating device comprising a position confining slot, a recovery spring, and a retaining member. The retaining member is formed of a press portion and a retaining portion and is urged by the recovery spring such that the retaining portion is retained by the ratchet portion so as to fix the movable joint member, and that the retaining portion is forced to move away from the ratchet portion at such time when the press portion of the retaining member is exerted on by an external force, thereby enabling the movable joint member to swivel.