A radiation imaging apparatus includes a grid holding unit including a grid for preventing scattering of X-rays, an imaging unit configured to capture an X-ray image, and a handle unit including a gripping handle. One of the grid holding unit, the imaging unit, and the handle unit includes a first detaching regulation unit configured to combine the grid holding unit and the imaging unit, a second detaching regulation unit configured to combine the imaging unit and the handle unit, a third detaching regulation unit configured to combine the grid holding unit and the handle unit, and an unlocking mechanism.