The separator for secondary battery, comprising: a porous substrate having a melting temperature or a decomposition temperature of 200° C. or more; and a resin member formed at least inside of the substrate in a plane section that occupies at least a part of a plane along with a thickness direction of the substrate; wherein said resin member is coated on inner surfaces of pores without completely blocking connecting paths that connects pores of the porous member, and wherein a distribution density of the resin member becomes lower toward inside of the substrate.