Abstract: A polarization film which has excellent polarizing ability and resistance to moisture and heat is described. The polarization film includes an oriented polyvinyl-alcohol-type film having iodine adsorbed thereon, and contains a zirconium compound or a manganese compound. The zirconium compound or the manganese compound is thought to prevent dissociation of a polyiodide ion such as I.sub.3.sup.- or I.sub.5.sup.- capable of providing the polarizing ability. The polarization film of the invention may be suitable for use in a variety of liquid crystal displays, including those which are used in severe environments, such as automotive display devices, and in ordinary household devices, for example word processors.