According to an aspect, an active matrix substrate of an X-ray imaging panel includes: an active matrix substrate having a pixel region including a plurality of pixels; and a scintillator that converts X-rays projected onto the X-ray imaging panel to scintillation light. The plurality of pixels include respective photoelectric conversion elements. The active matrix substrate further includes a first planarizing film that covers the photoelectric conversion elements, is formed from an organic resin film, and has a plurality of first contact holes and a first wiring line that is formed in the first contact holes and in a layer upper than the first planarizing film and connected to the photoelectric conversion elements within the first contact holes.