The micro-fabrication process of the homemade two-photon polymerization fabrication system is introduced, and the formability of the external gear set is studied at different exposure time. The two-photon polymerization micro-fabrication of the outer gear sets are realized in the photomer3015, and the microstructure of the gear sets is analyzed through scanning electron microscope (SEM). The results show that with the increase of exposure time, the formability of the gear sets is better. When the exposure time increases, the total fabrication time also increase. When the laser power is 0.3 mW and the exposure time is 10 ms, the two-photon polymerization micro-fabrication of the outer gear set with the tooth thickness of 2 mm and a resolution of 1.0 mm is successfully manufactured.