The invention discloses a digital display module device of a rivet / nut gun, which comprises a rivet / nut gun body and a digital display module device. The device comprises a power supply device, a pressure sensor, a central processing unit, a display, an input device, a position sensor and an alarm device. Air pressure or oil pressure in the rivet / nut gun body and moving position of a piston element are sensed; and pressure, pull, hyper-pressure maximum pressure value and accumulated working times are displayed on the display through logical operation program modules of pressure, pull, counting, hyper-pressure and stroke abnormality alarm, metering unit conversion and the like of the central processing unit. Therefore, a user can determine whether the current pull is enough to deal with a rivet or a nut to be pulled in time under the safe operating condition, and the device provides alarm under the abnormal condition.