Provided are a laminate film which enables to enhance luminance, and a backlight unit and a liquid crystal display device including this laminate film, as well as a method for producing this laminate film. Provided are laminate films including an optical functional layer and a barrier layer stacked on at least one surface of the optical functional layer, laminate films each having a film having a higher refractive index than a refractive index of the optical functional layer, on a lateral surface of the optical functional layer. It is preferable that the optical functional layer include at least one of a quantum dot and a quantum rod.