A method for producing surface convexes or concaves enabling easy and highly precise formation of desired convex/concave shapes using a photomask is provided.A mask member 20 having light transmitting sections and non-light transmitting sections is disposed over one side of a photosensitive film 10 consisting of a photosensitive resin composition with an interval with respect to the photosensitive film 10, and a light diffusing member 30 is disposed on the opposite side of the photosensitive film 10 across the mask member 20. Light is irradiated from a light source disposed on the opposite side of the mask member 20 across the light diffusing member 30 to subject the photosensitive film 10 to light exposure through the light diffusing member 30 and the light transmitting sections of the mask member 20. Exposed portions or unexposed portions of the photosensitive film 10 are removed by development to produce convexes or concaves on the photosensitive film 10 in shapes determined by shapes of the exposed portions or unexposed portions. In the light exposure, light exposure conditions such as haze of the light diffusing member 30 are controlled to control the shapes of the exposed portions or unexposed portions.