The tap safety cover conceals a rotating tap or the like to prevent a worker from contacting the sharp cutting edges of the tool during operation. The device includes a tool holder which secures in the chuck or bit holder of a rotary power tool. A hollow cylindrical barrel is affixed to the tool holder, with an extension sleeve telescoping from the barrel. The tap extends concentrically through the tool holder, barrel, and sleeve, and is completely covered when the sleeve is extended. A coil spring in the barrel urges the sleeve to a fully extended position, with the sleeve retracting as it is pushed back by the workpiece as the tap penetrates a previously drilled hole in the workpiece.