A radiation imaging apparatus includes a plurality of spaced apart imaging elements comprising each a plurality of pixels and an external terminal for external connection, wherein a lead constituting the external terminal is extended to the side portion opposite to a light receiving surface of each of the spaced apart imaging elements through a space between the adjacent imaging elements, a first planarizing layer is formed on the light receiving surface to be positioned at the same height as the external terminal or on the incidence side based on the height of the light receiving surface, and a wavelength converter is formed on the plurality of spaced apart imaging elements through a second planarizing layer formed on the external terminal and the first planarizing layer.