<p>Industrial robots are widely used as the processing equipment for freeform surface polishing. To ensure the corresponding polishing contact pressure, the desired polishing force values and polishing position/posture must be synchronously controlled. Aiming to solve the issue of non-synchronous control of polishing force, position and posture, this study proposes a force/position/posture synchronous control strategy for robotics polishing of freeform surface. A polishing force controllable end-effector is designed based on the 3-TPS 5-axis hybrid robot. The polishing force control system is developed as a subsystem of the robot control system. Synchronous interpolation algorithm for force/position/posture of variable force polishing is proposed to realize force/position/posture synchronous control. The experiments on variable force polishing adopting force/position/posture synchronous control are conducted on concave parabolic surfaces. The experimental results show that the polishing force tracks the changing requirements at different positions. The average error is within ± 0.1 N, and the absolute average error is between 0.3 N to 0.4 N. For freeform surface components with uneven margin distribution, the margin can be removed synchronously in proportion by the force/position/posture synchronous control. The synchronous control strategy of force/position/posture for freeform surfaces in robotic polishing process has strong universality, standardization and application.</p>