Abstract: In order to realize the high precision 3D reconstruction for deep-hole inner surface geometry, a 3D measurement system was built based on the structured light. First, the constitution and relevant measurement principle of the system were introduced, the assertion was proved that the distance between the image and the actual was approximately linear in a given range. The assertion lays a solid theoretical foundation for the following measurement. Then, the deep-hole model object and the model in which the corresponding inner surface was unfolded into a plane which were measured using the structured light. The measurement proves the feasibility of the measurement scheme and the actual effect of the measurement system. The measurement results show that the measurement scheme is feasible in theory, the measurement accuracy of the system can reach sub-pixel in practical applications and the absolute deviation is controlled within 0.034 7 mm range. Finally, in the actual measurement of the inner surface of the deep-hole parts inner surface, the high precision 3D reconstruction for deep-hole inner surface geometry was realized.