Abstract: Spaceflight mutation was carried out to improve Coenzyme Q10(CoQ10) yield to be utilized in industrial microbial fermentation. CoQ10 high yield mutants were screened from Rhodobacter sphaeroides that was collected from a recoverable satellite after a 15-day flight in space. High yield mutant strains were selected based on colony morphology, including colony size and color, and then screened using the method of shake flask fermentation. The CoQ10 production was measured using HPLC. The CoQ10 production of the mutant strain named "Shenzhou 6" reached (0.8+0.02)g/L, 33％ higher than the control group. The production could be increased with the optimization of fementation conditions and the strain could be utilized in the industrial microbial fermentation. Meanwhile, the result revealed that spaceflight showed multi-factor mutagenic effect on Rhodobacter sphaeroides compared to the traditional single-factor mutagenesis methods. It could increased CoQ10 production of isolated strains, and could be utilized in industrial microbial mutagenesis and breeding in the future.