To provide a portable cutting tool improved in work efficiency by preventing the scattering of chips.

A portable electric circular saw (a portable cutting tool) includes: a cutting tool body having a motor as a driving source and a saw blade (a cutting tool) 4 rotatively driven by the motor; and a base 1 for guiding the cutting tool body along the surface of material P to be cut, wherein a parallel ruler 12 can be mounted on the base 1. A dust guard 21 slidable parallel to the end face of the saw blade 4 and abutted on the end face of the saw blade 4 is fixed to a guide bar 14 passed through insert holes 15, 16 formed in the base 1 with a fixing screw (a fixing means) 22.