A binder, an electrode and a lithium secondary battery comprising the same, wherein the binder includes a first block including a polymer containing functional groups substitutable with lithium ions and a second block. The second block may include a polymer containing oxygen atoms in the main chain. With such a binder, it is possible to prevent the agglomeration of the slurry for preparing the electrode, thereby preventing the occurrence of cracks on the surface of the electrode and improving the life characteristics of the lithium secondary battery.