Abstract: A tobacco cell stain of HHDJY was selected by suspension cultare from 4 tobacco strains cultivated in South China on the level of CoQ10. By using this tobacco cell strain, the effectS of several plant growth regulation on the cell growth and content of CoQ10 were studied. The growth of the cells was greatly enhanced by 0.1 ~ 0. 2 mg/L BA and KT. 2,4-D could increase the content of CoQ10 but becampe unfavorable to cell growth when the concentration was high. IAA and NAA had no effect on cell growth and content of CoQ10. Morcover, CoQ10 crystal was obtained from suspension cells with acetone abstraction,petrolembenzine extraction and silica chromatography. The recovery of CoQ10 was 59. 2%, and the purity reached 97. 7 %.