An electric power tool comprises an electrical connection part which allows connection with relative less efforts. A grinder comprises a terminal unit (23) and a switch box (24). A signal line (23g, 23s, 23i) transmitting pressing start signals and on signals are a power wire (23p) for power supply are connected to the terminal unit. The terminal unit (23) is mounted on the switch box and comprises a signal terminal (82g, 82s, 82i) connected to the signal line (23g, 23s, 23i) and a power terminal (82p) connected to the power wire (23p). The switch box (24) has a switch side signal terminal (102g, 102s, 102i) connected to the signal terminal in the terminal unit (23) mounted on the switch box and a switch side power terminal (24c) connected to the power terminal (82p) in the terminal unit (23) mounted on the switch box.