A total knee arthroplasty robot auxiliary system, comprising: a preoperative planning system, configured to formulate a preoperative prosthesis plan based on user input, wherein the preoperative prosthesis plan data comprises an image of a knee joint of a patient and prosthesis data placed relative to the image; an intraoperative planning system, configured to formulate an intraoperative prosthesis plan, wherein the image in the preoperative prosthesis plan and a knee joint surface contour of the patient determined in an operation are subjected to image registration, and the intraoperative planning system is further configured to acquire knee joint dynamic spacing force line data at continuous flexion-extension angles, and visually display a graph of the dynamic spacing force line data, and to adjust a prosthesis plan according to the visual display of the graph of the dynamic spacing force line data and user interaction therewith, so as to obtain the intraoperative plan; and an executing system, configured such that a bone-cutting guide mounted at an operating end of a mechanical arm of a surgical robot is guided to be located in a planned predetermined position according to the intraoperative prosthesis plan, and the bone-cutting guide is configured to locate a bone-cutting saw; wherein the preoperative planning system and the intraoperative planning system are arranged in an upper controller, the executing system is arranged in the surgical robot, and the upper controller is configured to transmit the intraoperative plan to the surgical robot, so that the surgical robot can execute a corresponding operation according to the plan, wherein the intraoperative planning system comprises a positioning system, the positioning system comprises a femur tracer, a tibia tracer and a navigation camera, the femur tracer and the tibia tracer are respectively configured to be arranged at a femur and a tibia of the knee joint of the patient, and the navigation camera is configured to cooperate with the femur tracer and the tibia tracer to acquire and record motion track information of the knee joint in a continuous lower limb flexion-extension process; and the upper controller is in communication connection to the femur tracer, the tibia tracer and the navigation camera, and is configured to calculate a spacing and a force line angle at continuous lower limb flexion-extension angles according to the motion track information so as to acquire knee joint dynamic spacing force line data at the continuous flexion-extension angles. a preoperative planning system, configured to formulate a preoperative prosthesis plan based on user input, wherein the preoperative prosthesis plan data comprises an image of a knee joint of a patient and prosthesis data placed relative to the image; an intraoperative planning system, configured to formulate an intraoperative prosthesis plan, wherein the image in the preoperative prosthesis plan and a knee joint surface contour of the patient determined in an operation are subjected to image registration, and the intraoperative planning system is further configured to acquire knee joint dynamic spacing force line data at continuous flexion-extension angles, and visually display a graph of the dynamic spacing force line data, and to adjust a prosthesis plan according to the visual display of the graph of the dynamic spacing force line data and user interaction therewith, so as to obtain the intraoperative plan; and an executing system, configured such that a bone-cutting guide mounted at an operating end of a mechanical arm of a surgical robot is guided to be located in a planned predetermined position according to the intraoperative prosthesis plan, and the bone-cutting guide is configured to locate a bone-cutting saw; wherein the preoperative planning system and the intraoperative planning system are arranged in an upper controller, the executing system is arranged in the surgical robot, and the upper controller is configured to transmit the intraoperative plan to the surgical robot, so that the surgical robot can execute a corresponding operation according to the plan, wherein the intraoperative planning system comprises a positioning system, the positioning system comprises a femur tracer, a tibia tracer and a navigation camera, the femur tracer and the tibia tracer are respectively configured to be arranged at a femur and a tibia of the knee joint of the patient, and the navigation camera is configured to cooperate with the femur tracer and the tibia tracer to acquire and record motion track information of the knee joint in a continuous lower limb flexion-extension process; and the upper controller is in communication connection to the femur tracer, the tibia tracer and the navigation camera, and is configured to calculate a spacing and a force line angle at continuous lower limb flexion-extension angles according to the motion track information so as to acquire knee joint dynamic spacing force line data at the continuous flexion-extension angles.