The invention relates to an automatic glue brushing machine. The automatic glue brushing machine comprises a clamping mechanism for clamping workpieces, a glue conveying mechanism for conveying glue to the surfaces of the workpieces, a glue brushing mechanism for brushing the glue conveyed to the surfaces of the workpieces along the circumferential faces of the workpieces, and a first driving mechanism for driving a rotating disc to rotate so as to enable a glue brushing assembly to rotate along the circumferential faces of the workpieces, wherein the glue brushing mechanism comprises a support, the rotating disc and the glue brushing assembly, the rotating disc is rotatably arranged on the support, and the glue brushing assembly is arranged on the rotating disc. The automatic glue brushing machine has the characteristic of high automation degree.