A ratchet wrench includes a driving device having first and second sides spaced along a rotating axis. A compartment extends from the first side through the second side. A drive member is received in the compartment and includes an end for driving a tool. A ledge is formed on an inner periphery of an end of the compartment at the second side. A pressing rod extends into the drive member via the end of the compartment at the second side. The pressing rod is movable relative to the drive member along the rotating axis to control engagement with or detachment from the tool. A dustproof ring is mounted between the ledge and the pressing rod. The dustproof ring includes an outer side and an inner side. The outer side presses against an abutment portion of the ledge. The inner side presses against the pressing rod.