The invention aims to provide a screw feeding mechanism of an automatic screwdriving machine for electric meter assembly. The screw feeding mechanism is simple and stable in structure, is used for rapidly feeding screws and screening defective screws out and guarantees rapid and efficient screw feeding. In order to achieve the purposes, the screw feeding mechanism of the automatic screwdriving machine for the electric meter assembly comprises a screw bin, wherein four screw feeding channels are formed in the screw bin, an upright screening device is arranged on each channel, the tail end of each upright screening device is connected with a direct screw sending channel, a screening brush is arranged in the position where each upright screening device and the corresponding direct screw sending channel are connected, and each direct screw sending channel is connected to a corresponding electric screwdriver. With the adoption of the technical scheme, rapid screw feeding can be realized, and the defective screws are rejected in a screw feeding process; the product quality reduction or the production equipment damage caused by the defective screws is avoided; and more importantly, the feeding synchronism is not influenced even though the defective screws exist in one channel.