Auxiliary supporting device for milling machine

An auxiliary supporting device for a milling machine comprises a base, supporting wheels, a lower support plate and an upper support plate for fixing a to-be-processed workpiece. The auxiliary supporting device is characterized in that the base is provided with a guide rail, four supporting wheels are fixed on the lower support plate, the lower support plate is provided with a lower shaft hole fixed with the lower end of a supporting shaft, the upper support plate is provided with an upper shaft hole in clearance fit with the upper end of the supporting shaft, a pressure plate for limiting the upper support plate is arranged at the top end of the supporting shaft, and the upper support plate is provided with a clamp structure. According to the auxiliary supporting device for the milling machine, the processed workpiece is supported, automatic milling processing of the workpiece is achieved, and the width of the workpiece processed through the milling machine is increased. By rotation of the upper support plat