To improve the output characteristics of green light lasers, a volume Bragg grating external cavity second harmonic generation semiconductor laser is designed. A reflective volume Bragg grating was used as a feedback element to construct an external cavity semiconductor laser, and a lithium triborate crystal was used for second harmonic generation. The influence of the beam and spectral characteristics of the fundamental frequency light on the beam and spectral characteristics of the frequency doubling light was studied. The experimental results showed that when volume Bragg grating for external cavity mode locking was used, the obtained second harmonic generation also could achieve narrow bandwidth output, and the far field distribution of second harmonic generation was consistent with that of fundamental frequency light. A volume Bragg grating with a diffraction efficiency of 10% was used as an external cavity output mirror. The output wavelength of the semiconductor laser could be stably locked at 1 064 nm. The obtained second harmonic generation wavelength could be stabilized around 532 nm. The spectral linewidth was compressed to about 0.4 nm, and the output power could reach 73 mW.