The missile-borne laser active imaging guidance technology is one of the most important laser guidance technology in the modern war. Among them，the development of the missile-borne active imaging laser is current research hotspot and difficulty. A high beam quality laser of 1 064 nm used in laser missile-borne active imaging was reported. The pulse width of 3.005 ns，the pulse energy of 3.36 mJ and the spectral width of 78 pm at the repetition rate of 100 Hz were obtained by diode in-band end-pumped Nd：YAG crystal and integrated design. The quality of laser beam M2 is 1.327 in X direction and 1.354 in Y direction through in-band pumping and cavity optimization design. Imaging results show that, the successful development of the laser have directive meanings for the parameter design of high beam quality solid state laser and engineering application of laser active imaging.