A switch device includes a shell, a ratchet wheel, a first pawl member, a second pawl member, a first biasing member, a second biasing member, a switch shaft, and a stop member. The shafting shaft is disposed to turnably engage a central segment of the stop member. Two lateral segments of the stop member are disposed respectively above the first and second pawl members, and respectively have two abutment edges that are disposed opposite to the ratchet wheel, and that are configured to be brought into abutting engagement with a surrounding wall of the shell so as to prevent the switch shaft from pulling out of the shell. A ratchet wrench having the switch device is also disclosed.