There are provided an optical compensation film including an alignment film whose adhesiveness to a substrate and a liquid crystal layer and alignment property are excellent when a novel substrate is used to solve the problem regarding deteriorated durability being caused when a retardation film including a liquid crystal film is used under a hot and humid environment, and an integrated polarizing plate comprising the same. The O-plate includes a substrate; an alignment film prepared by coating the substrate with a composition for an alignment film that is composed of polyvinyl alcohol, a multifunctional acrylate monomer, a compatibilizing agent, a photo initiator and a solvent, followed by undergoing drying, curing and rubbing processes; and a splay-aligned liquid crystal film formed on the alignment film.