Provided are: a cell population which is essentially formed from mammalian cells in which cell surface markers CD31 and CD200 are positive, and cell surface marker CD45 is negative； a cell population which is essentially formed from mammalian cells in which cell surface markers CD31, CD157, and CD200 are positive, and cell surface marker CD45 is negative； mammalian vascular endothelial stem cells in which cell surface marker CD31 is positive, cell surface marker CD157 and/or cell surface marker CD200 are/is positive, and cell surface marker CD45 is negative； and a revascularizing pharmaceutical having, as an active ingredient, the cell populations or the vascular endothelial stem cells.
