To provide a polarizing plate including a polarizing layer containing anisotropic metal nanoparticles produced by reducing a metal ion in a liquid crystal matrix. An embodiment in which the liquid crystal matrix is characterized in that molecules of a liquid crystal compound are fixed in an alignment state of any one of substantially horizontal alignment, substantially vertical alignment, diagonal alignment, hybrid alignment and spiral alignment; an embodiment in which the reduction is at least one of photoreduction, thermal reduction and chemical reduction; and the like are favorable.