Abstract: To acquire high power and high efficiency mid-infrared laser output, using double acousto-optic Q-switched crystal, through high repetition rate drive Qswitched synchronization technology and LD-side-pumped two-rod series connection technology, high power and high beam quality 1.06 m laser twoport output was acquired, laser output of four beams was got by exterior polarizer. Using wave-plate polarization rotation principle, consistent polarization laser output of four beams could be realized, PPLT was pumped to get high power 3 m~5 m Mid-IR laser output. As the input current was 30 A and the Qswitched frequency was 10 kHz, the highest out power of 3.9 m laser was 10.6 W, conversion efficiency of 1.06 m ~3.9 m laser was 9.5%. Experiment results indicate that using double acousto-optic Q-switched technology and LD-side-pumped two-rod series connection technology, high repetition 1.06 m polarizer laser output of four beams can be realized, and pumping PPLT can gain high power 3.9 m mid-infrared laser output.