A force-balanced MEMS sensor is developed to measure the forces between two surfaces with controllable distance. Its mechanical structure is like a pendulous micromachined accelerometer, and it is designed as a closed-loop system with electrostatic force feedback. The surface force on the sensor probe is balanced by the electrostatic force and the probe operates without displacement. This method avoids the displacement of the conventional cantilever, and the distance between the two surfaces is precisely controlled during the measurement. Experiments on surface force measurements between a probe surface and a ball surface are performed, and the attractive force and adhesion force between the two surfaces are measured under a precise distance controlled by a nanopositioner.