Objective:To observe influence of mitochondrial manganese superoxide dismutase (MnSOD ) on vascular alkaline phosphatase (ALP) activity ,transcription factor :Runx2 and Osterix expression levels in MnSOD‐Tg mice model of vascular calcification .Methods :A total of 20 wild type (WT) mice were selected as WT group and 20 Mn‐SOD‐Tg mice were enrolled as MnSOD‐Tg group ,then mice model of vascular calcification was established .Vascu‐lar ALP activity ,expression levels of transcription factor Runx2 and Osterix were compared and analyzed between two groups .Results:After successful model establishment ,compared with WT group ,there were significant reduc‐tions in ALP activity [ (75.89 ± 4.17) vs .(61.32 ± 3.12)] , expression levels of transcription factor Runx2 [ (0.928 ± 0.016) vs .(0.694 ± 0.007)] and Osterix [ (0.472 ± 0.036) vs .(0.257 ± 0.013)] in MnSOD‐Tg group , P<0.01 all .Conclusion:Manganese superoxide dismutase may be improving atherosclerosis via reducing activity of vascular alkaline phosphatase ,expression levels of transcription factor Runx2 and Osterix .