Objective：To investigate whether pyrroloquinoline quinone（PQQ） plays a treatment role in premature aging of skin in Bmi1-/- mice by inhibiting oxidative stress. Methods：We paired with littermates Bmi-1+/- between male and female mice，and selected the mice at the age of 7 weeks：wild type mice and normal diet （10 mice），Bmi1-/- mice and normal diet （10 mice），Bmi1-/- mice and add PQQ diet （10 mice）. HE staining，histochemistry，immunohistochemistry，and flow cytometry were peformed. Results：Compared with BKO mice，PQQ partially rescued total body phenotype，made hair of skin smooth，increased body weight and prolonged survival time. Compared skin thickness of PQQ+BKO mice ［（142.65±0.25）μm］ to BKO mice ［（78.45±0.35）μm］，the difference was statistically significant （P<0.01）. The percentage of total collagen positive area of skin in the PQQ+BKO group ［（25.64±0.28）%］ was significantly different from that in the BKO group ［（14.87±0.47）%,P<0.01］. The percentage of skin PCNA positive cells in the PQQ+BKO group ［（18.54±0.37）%］ was significantly different from that in the BKO group ［（5.85±0.64）%,P<0.01］. The positive area of skin fibrosis in the PQQ+BKO group ［（48.64±0.28）%］ was significantly different from that in the BKO group ［（87.64±0.46）%,P<0.01］. Compared with BKO mice （427.80±0.63），the levels of ROS in the skin of the PQQ+BKO group （298.17±0.25） were significantly decreased，and the difference was statistically significant（P<0.01）. Conclusion：The results of these studies indicated that PQQ played a role in protecting premature aging of skin induced by Bmi-1 defection through multiple aspects，such as promoting skin cell proliferation，reducing skin tissue fibrosis，scavenging ROS levels of oxygen free radical.