An object of the present invention is to provide an optical film having an optically anisotropic layer having excellent durability, and a polarizing plate and an image display device using the same. This optical film of the present invention is an optical film at least having an optically anisotropic layer, in which the optically anisotropic layer is a layer obtained by polymerizing a polymerizable liquid crystal composition containing a predetermined liquid crystal compound and a polymerization initiator, and the optically anisotropic layer has a density of 1.20 g/cm3 or more and a crosslinking point density of 0.0016 mol/cm3 or more.