Objective To establish a biomechanical robot-based testing device to carry out biomechanical experiment of human spine.Method Use the solidwork software to design the fixture and adopt the socket programming to realize the network communications between PC and robot controller through Visual C + +6.0 platform, reading the position and rotation of the robot-end implementation.A data acquisition card is inserted inside the PC to read the force(torque) in three-dimensional space.The pose and torque data are put into the control procedures and handled, drawing the force-displacement two-dimensional curves to help analyze the experimental results.Result Develop a biomechanical robot-based testing device and the corresponding control software(force control, displacement control, a mixed force/ displacement control) and various kinds of monitoring program.Conclusion Design a new experimental testing device based on the computer control of the 6-DOF Robot and use hybrid force-displacement control method to load the human spine, which could have the organizational structure and the force state of the FSU well tested, and it is easy to identify the spinal degeneration and the load-bearing impact on the organizational structure of the FSU after various types of surgery.