Provided is a thin wavelength conversion film in which a phosphor can be uniformly dispersed and deterioration of the phosphor caused by oxygen can also be prevented; and a backlight unit including the wavelength conversion film. The wavelength conversion film includes a wavelength conversion layer and a substrate, in which the wavelength conversion layer includes a binder and particles including a phosphor, an oxygen permeability coefficient of the binder is 0.01 (cc·mm)/(m2·atm) or lower, an oxygen permeability coefficient of the matrix is 10 to 1000 (cc·mm)/(m2·day·atm), and a content of the particles in the wavelength conversion layer is 3 to 30 vol %.