Separator for secondary battery, method for manufacturing the same and secondary battery including the same

A separator for a secondary battery, including a porous polymer substrate; a porous coating layer on at least one surface of the porous polymer substrate. The porous coating layer includes a plurality of inorganic particles and a first binder polymer that interconnects and fixes the inorganic particles; and an adhesive layer on a surface of the porous coating layer opposite to the porous polymer substrate. The adhesive layer includes a second binder polymer, and the adhesive layer includes a first layer in contact with the surface of the porous coating layer opposite to the porous polymer substrate, and a second layer integrated with the first layer and the second layer faces an electrode. The second layer has an average pore size larger than the average pore size of the first layer. The separator for a secondary battery can improve the problem related with resistance, while ensuring adhesion to an electrode.