The invention provides a casting mold assembling box pressing fastener which comprises a trough type fastener and a screw rod, wherein a cantilever beam is arranged at the upper end of the trough type fastener, and a hook part is arranged at the lower end of the trough type fastener; a screw hole I is longitudinally formed in the cantilever beam; the screw rod penetrates through the screw hole I and is meshed with the cantilever beam; a clamping sleeve is arranged on the upper part of the screw rod in a sleeving manner; a through hole I is transversely formed in the clamping sleeve; an operating handle transversely penetrates through the through hole I; and a pressing part is arranged on the lower part of the screw rod and comprises a special nut, a round nut, a ball and a pressure head screw. According to the casting mold assembling box pressing fastener, wear of two iron mold guide rail surfaces or two sand box surfaces caused by the rotating process of the screw rod and thermal wear of the screw rod thread and nut thread can be relieved, so that the service life of an iron mold or a sand box or a box pressing tool is prolonged, and the labor intensity of workers is alleviated.