ELECTRIC-POWER-DRIVEN WORKING DEVICE

A chainsaw 1 (electric-power-driven working device) comprises a body case 10， a cutting attachment 20 (work tool)， a motor 30 and a battery 90. A front portion 11a of the body case 10 houses the motor 30 and a battery mount-and-release portion 12 is formed on a rear portion 11b of the body case 10. The battery 90 mounted on the battery mount-and-release portion 12 extends in an upper-lower direction across and over a middle portion in a height direction of the rear portion 11b of the body case 10. The side handle 50 arranged to a side face of the body case 10 extends from the front portion 11a to the rear portion 11b of the body case 10. A rear end portion 52 of the side handle is disposed rearward of and below an output shaft 31 of the motor 30.