The present invention relates to a multi-layered microporous polyolefin film for a battery separator and a method for preparing the same. The microporous multi-layered film of the present invention has a characteristics to have both the low shutdown temperature conferred by the polyethylene and the high melt fracture temperature conferred by the polypropylene and heat-resistant filler. In addition, it has the high strength and stability conferred by the micropores prepared under wet process and the high permeability and high strength conferred by the macropores prepared under dry process. Therefore, this multi-layered film can be used effectively to manufacture a secondary battery with high capacity and high power.