This invention relates to a method for isolating smooth muscle stem cells derived from mammalian smooth muscle comprising bringing mammalian smooth muscle cells into contact with a fluorescence-labeled anti-CD45 antibody, anti-CD34 antibody, and anti-CD49f antibody, and isolating cells that would not bind to the anti-CD45 antibody but would bind to the anti-CD34 antibody and the anti-CD49f antibody.