The invention discloses a punching machine with an automatic feeding function. The punching machine with the automatic feeding function is characterized in that the punching machine comprises a punching mechanism, a control device, a feeding machine frame and an automatic feeding mechanism arranged on the feeding machine frame, the automatic feeding mechanism comprises a carrying roller installed on the feeding machine frame, a linear guideway, and a traveling mechanism arranged on the linear guideway, a clamping mechanism is arranged on the traveling mechanism, the traveling mechanism comprises a trailer wagon and a servo motor driving the trailer wagon to move along the linear guideway, the servo motor is connected with the control device, the control device controls the moving state of the trailer wagon, the punching mechanism comprises a supporting platform, a pressing cylinder, an upper puncher pin, and a lower die core arranged in the inner cavity of a sectional material, a recess corresponding to the upper puncher pin is formed in the upper surface of the lower die core, a die inner core pulling rod is arranged on the feeding machine frame, the lower die core is fixed at one end of the die inner core pulling rod, and the die inner core pulling rod is parallel to the linear guideway and penetrates through the trailer wagon. The punching machine with the automatic feeding function is simple in operation, high in production efficiency, and high in product accuracy.