The utility model discloses an automatic reversing sand mould, which comprises an upper mould box, a lower mould box and sand, and is characterized in that the upper mould box and the lower mould box are connected through a hinge structure; a rotating shaft 3 used for connecting the upper mould box and the lower mould box is connected onto a servo motor; a base plate is arranged at the bottom of the lower mould box; a bulge is arranged on the side edge at the front end of the lower mould box, and is matched with a buckle structure arranged on the base plate. The automatic reversing sand mould overcomes deficiencies in the prior art, is reasonable in structural design, is stable in positioning of an upper mould and a lower mould, is convenient to maintain and good in overall stability, saves labor force, improves the production efficiency and is wide in application range as the upper mould box is connected with the lower mould box through the hinge structure and the upper mould box is driven to be turned over through the motor.