Based on the analysis of the influence of optical system on tracking detection and combined with the instrumental functions, a smart method based on glued lens is proposed to reduce tracking offsets. The tracking optical path in the femtosecond laser tracker is optimized. At the same time, the optical path for collimation and expanding is improved, and the optical system is refined. The influence mechanism of receiving laser power and stray light in the optimized optical system on tracking detection is analyzed in detail. Based on the optimal design of the optical system, the experimental system is established and the detection experiment is conducted. The research results show that the tracking detection accuracy can reach 3 μm after compensation, which meets the precision tracking requirements of instruments.