An electric work vehicle is provided in which the length of a high-tension cable connecting an electric motor included in a slewing motor with an inverter for controlling the electric motor can be set to be comparatively short. A region on a main frame is divided into three regions consisting of a center region, a first side region, and a second side region, via a first vertical rib and a second vertical rib. A slewing hydraulic motor and a slew assist electric motor, which constitute the slewing motor, are disposed in the center region, and an inverter for controlling the slew assist electric motor is disposed in a position near the second vertical rib in a second tool chamber provided in the second side region.