Abstract: An adaptive impedance control algorithm with online adjustment and offline optimization of impedance parameters was designed for the constant force polishing needs of robots to achieve polishing force control. The adaptive impedance control algorithm takes stiffness parameters as time-varying parameters and adjusts them online in real-time based on the grinding contact force to eliminate steady-state errors during the grinding process. Aiming at the problem of difficult tuning of damping and inertia parameters, an improved particle swarm optimization algorithm is adopted for offline optimization of impedance parameters to reduce system overshoot and adjustment time. A constant force polishing simulation of the robot was conducted, and the simulation results showed that the method proposed in this paper can comprehensively improve the constant force control performance of the robot. The robot constant force polishing experiment was conducted, and the experimental results showed that the method proposed in this paper can effectively improve the surface quality of robot polishing.