The invention provides a stapler with a suture fixing device. The stapler comprises a gun body, a center shaft arranged in the gun body, a nail abutting base and a tail rotary knob, wherein the nail abutting base and the tail rotary knob are connected with the two ends of the center shaft respectively. A suture fixing piece capable of moving synchronously with the center shaft is arranged on the center shaft. The stapler is placed at the affected part, then a suture is tensioned, one end of the suture is fixed to the suture fixing piece after being knotted, then a doctor holds the gun body with one hand and rotates the tail rotary knob with the other hand, and when rotated, the tail rotary knob drives the center shaft to move towards the tail rotary knob; due to the fact that the suture fixing piece capable of moving synchronously with the center shaft is arranged on the center shaft, the suture fixing piece drives the suture, the suture pulls the purse string suture portion, and when the tail rotary knob rotates to a proper position, the doctor grasps a percussion handle on the gun body to complete incision suture. According to the stapler, the doctor does not need to pull the suture with fingers of one hand, so that the fingers of the hand are freed, and the stapler is easier to operate.