Abstract: The present invention refers to a transmission mechanism of an eyebrow tattoo machine, which includes an eccentric rotation shaft connected to a driving axle of a motor and having a bottom end configured to rotate eccentrically with respect to the driving axle, an upper bearing coupled with the bottom end of the eccentric rotation shaft, a position-limiting cover longitudinally provided with a position-limiting groove, and a swinging rod element mounted to the upper bearing and provided with a swinging rod and a position-limiting rod on two sides respectively. Since the position-limiting rod is only allowed to swing up and down in the position-limiting groove when the eccentric rotation shaft drives the upper bearing and the swinging rod element, the end of the swinging rod away from the upper bearing can swing up and down and then drive a tattoo needle to move vertically up and down through a lateral bearing.