The invention discloses a terminal pressing device for wire harness processing. The terminal pressing device comprises a fixation plate. The fixation plate is fixedly mounted on a base through support columns fixedly connected at the two sides of the bottom portion. One support column is fixedly equipped with a start point sensor and an end point sensor. The top portion of the fixation plate is fixedly equipped with a cylinder. A push rod of the cylinder passes through the fixation plate and is fixedly connected with a sliding plate. The sliding plate is mounted on a slide rod arranged between the fixation plate and the base. The right end of the sliding plate is fixedly equipped with a sensor sheet. A stop block arranged in a groove is fixedly arranged on the base. Clips arranged in the groove are fixedly arranged on a connection rod. The top portion of a control panel is fixedly equipped with a buzzer and an alarm lamp. A standby button, a stop button, a work button and an emergency stop button under a display screen are fixedly arranged on the control panel. The terminal pressing device is novel in structure, practical in function and convenient to operate, and can press terminals well during wire harness processing.