To provide an X-ray apparatus capable of minimizing the power consumption of a CPU inside a controller and the power consumption for driving an HDD, preventing the consumption of a battery and increasing the number of radiographing in use in round of visits which an AC power source can not be obtained.

In the X-ray apparatus constituted of a flat sensor panel for radiographing X-ray images, the controller for preserving radiographed images and performing an image processing and the battery for driving them, a means for detecting whether or not the AC power source is supplied is provided, and in the case that the AC power source is not supplied, only the images acquired from the flat sensor panel are preserved and the image processing is not performed. In this case, a mode of preserving the images acquired from the flat sensor panel only and not performing the image processing is provided.