PURPOSE: To contrive the improvement of working efficiency, the reduction of equipment cost, the stabilization of quality and the improvement of working environment by using a die for trimming press and the mechanism for executing punching, work of deburring on the outer periphery and correction of the flatness of a surface in one process of a trimming work to a flat plate-like die casting product.

CONSTITUTION: The trimming device is constituted of an upper die bolster 1, hydraulic cylinder 2, lower die bolster 6, upper die and lower die 5 of the press die 3, upper die cutting blade 4, lower die cutting blade 9, stopper 7, guide bar 8 and side support bar 10. Further, a rubber 13, rubber pusher 14 and rubber support 15 for correcting the surface are built in the trimming device.