In order to describe the relationship between the incident angle of Cube Corner Retro-reflector (CCR) and the measurement accuracy of CCR used in laser tracker system, the working principle and reflective characteristic of CCR were analyzed. A novel approach was proposed to determine the effective reflection area of CCR with an arbitrary incident angle and then the formula of ray cross section of CCR with varying incident angle was derived according to the effective reflection area. Accordingly, the relationship between CCR measuring accuracy and incident angle was established. The experimental results demonstrate that the CCR measuring accuracy reduces as the increase of incident angle, the CCR measuring error is the largest when the maximal incident angle is reached. The measuring error of CCR at maximal incident angle of ±35.26° is 0.050 mm, but the measuring accuracies of CCR are better than 0.010 mm when the incident angle are within ±20°, and the measuring accuracy and the stability are best only when the incident angles are within ±15°. The results show that CCR can maintain the manufacture specifications of laser tracking system only when the incident angles are within ±20°, which provides a very useful guidance for design and application for CCR.