To provide a fastener driving tool disposed with a blocking surface that prevents a muzzle part from displacing in a ready-to-fire position on a driven part during fasteners-empty condition.

This fastener driving tool is provided with a tool body, the muzzle part 44 extending forwardly from the tool body and being displaceable into the ready-to-fire position, a magazine for holding the fastener 90 coupled to the muzzle part 44, and the driven part 110 energizing the fastener in the magazine. The driven part 110 is provided with the blocking surface that blocks the muzzle part 44 during fastener-empty condition and prevents the muzzle part 44 from displacing into the ready-to-fire position.