The present disclosure relates to a separator for a lithium secondary battery comprising a porous substrate, and a porous coating layer disposed on at least one surface of the porous substrate and comprising inorganic particles and binder polymer, wherein the binder polymer is terpolymer including 65 to 90 weight % of a repeat unit derived from vinylidenefluoride (VDF), 1 to 28 weight % of a repeat unit derived from hexafluoropropylene (HFP) and 5 to 28 weight % of a repeat unit derived from chlorotrifluoroethylene (CTFE), and the separator has adhesiveness towards electrode ranging from 30 gf/25 mm to 150 gf/25 mm and machine direction (MD) thermal shrinkage of 1 to 18% and transverse direction (TD) thermal shrinkage of 1 to 17%, and a lithium secondary battery comprising the same, wherein the separator has uniform micropores on the surface, and thus has the increased adhesive surface area with electrode and consequential improved adhesiveness towards electrode.