The invention provides a power-driven plant pruning machine. The power-driven plant pruning machine is composed of the following interconnected components: a direct-current motor, a jagged circular blade, a battery, a motor fixing shell, a battery fixing shell, a power line, a power switch and a handle, wherein the battery with a voltage of 12 volts and capacity of 20 amperes supplies power for the power-driven plant pruning machine and drives the direct-current motor with rate voltage of 12 volts and rated power of 450 watts; the motor rotating at a high speed drives the jagged circular blade arranged on the exposed motor axle to spin at a high speed, and the blade cuts plants off as soon as the blade touches the plants; the power switch of the machine is installed above the front of the handle, and the power line passes through the hollow cavity of the handle and is separately connected with the motor and the battery; the handle, the motor shell and the battery shell are made of high-strength plastic materials, and a protecting cover is made of stainless steel sheet; and a charging jack is arranged in the lower part of the outer side of the battery shell and used for connection of an external charger for charging of the battery. The power-driven plant pruning machine has the advantages of small size, light weight, simple structure, convenient operation, high work efficiency, good pruning quality, conservation of effort and labor and wide application range.