Provided is a wavelength conversion member, including: a wavelength conversion layer containing a quantum dot which is excited by excitation light and emits fluorescent light; and an adjacent layer directly laminated on the wavelength conversion layer, in which the shape of an interface between the wavelength conversion layer and the adjacent layer includes an irregular shape formed of a concave portion and a convex portion. Provided are a backlight unit, a polarizing plate, a liquid crystal panel, and a liquid crystal display device: including the wavelength conversion member.