Objective To investigate the effect of single dose intraosseous injection of simvastatin on tumor vascular structure and function in murine breast cancer. Methods BALB/c mice and 4T1 murine breast cancer cells were used to establish a subcutaneous xenograft model. The mouse model of orthotopic breast cancer received intraosseous injection of a single dose of simvastatin (50 μg) or vehicle only. Frozen tumor tissue sections were prepared for co-immunostained with CD31 and α-SMA. Evans blue dye was injected into the tail vein to observe the vascular permeability. The expression level of HIF-1α was detected by immunohistochemistry. Results Immunofluorescence dual staining showed that intraosseous injection of simvastatin increased the number of perivascular pericytes in the tumor vessel(P < 0.05), Evans blue dye content showed that in vivo vessel permeability in the tumor tissue was significantly decreased(P < 0.05),and the immunohistochemistry results showed that local hypoxic area was significantly improved. Conclusions Single dose intraosseous injection of simvastatin can promote the normalization of tumor vasculature by improving the coverage of pericytes.