A micro-ball tapping probe is proposed for the form measurement of the micro-structured surface with high-aspect-ratio features. The micro-ball tapping probe is composed of a micro-ball stylus, a PZT actuator and an adapter. The micro-ball stylus consists of a micro-ball with a diameter of 50 μm, and a glass tube with a cone angle of 10 degrees. The micro-ball tapping probe was employed by a contact type air-bearing displacement sensor. Series of experiments were carried out to confirm the feasibility and performance of the proposed micro-ball tapping probe, including the strength test, the frequency characteristic test, the measurement force test and the surface form measurement for a micro-structured surface. Experimental results revealed that the micro-ball tapping probe is suitable for the form measurement of the micro-structured surface with high-aspect-ratio features.