An X-ray sensing device includes a photosensitive element, lead-containing glass, and an X-ray conversion structure. The photosensitive element is configured to sense light having a first wavelength. The lead-containing glass overlaps the photosensitive element. The X-ray conversion structure is disposed on the lead-containing glass. The lead-containing glass is located between the photosensitive element and the X-ray conversion structure. The X-ray conversion structure is configured to at least partially convert X-rays into light having the first wavelength.