To detect the degree of abrasion in a clutch and a brake without disassembling a clutch brake.

A wet clutch brake device of a mechanical press comprises a clutch 8 placed between a flywheel 7, connected to a main motor side, and a rotation shaft 4, connected to a main gear side, both of which are connected by the air supplied to the inside of a cylinder 12a and cut by a return spring 17, and a brake 9 which is released by the air and controlled by the return spring 17. The abrasion of linings 8c, 9c of the clutch 8 and the brake 9 is detected, without disassembling a clutch brake, from the deviation obtained by a measurement of at least either one of the time required for an air inside of the cylinder 12a reaches up to a given pressure since the start of air supply the time required for the pressure inside of the cylinder 12a reaches down to almost 0 after the start of exhaust, and by comparison of either one of the above two with the time set in advance is necessary for air supply or exhaust according to the abrasion degree of the linings 8c, 9c.