A radiation imaging apparatus comprising an image capturing device and a controller, the image capturing device including a sensor array where a plurality of sensors are arranged in an array, and the controller performing a control so as to drive the image capturing device in response to a trigger, wherein the controller is configured to: perform radiographic imaging, by executing repetitively an operation for obtaining image data of one frame from the sensor array at a period corresponding to a predetermined frame rate, the operation being performed by driving the image capturing device so as to be synchronized with one radiation irradiation for the sensor array, shift to a non-capturing mode upon receiving an instruction representing a suspension of the radiographic imaging, shift to a capturing mode upon receiving an instruction representing a start of the radiographic imaging, and drive, in the capturing mode, the image capturing device using a synchronization signal (SYNC) as the trigger, the synchronization signal (SYNC) being for a synchronous controlling between the operation and the radiation irradiation repeated at the period, characterized in that, the controller comprises a signal generator configured to generate another signal (SYNCX) differing from the synchronization signal (SYNC) when the controller is in the non-capturing mode, and the controller, in the non-capturing mode, is configured to drive the image capturing device using the other signal (SYNCX) as the trigger instead of using the synchronization signal (SYNC), thereby suppressing lowering of a temperature of the sensor array in the non-capturing mode from the temperature of the sensor array in the capturing mode, to prevent power consumption of the image capturing device from lowering. perform radiographic imaging, by executing repetitively an operation for obtaining image data of one frame from the sensor array at a period corresponding to a predetermined frame rate, the operation being performed by driving the image capturing device so as to be synchronized with one radiation irradiation for the sensor array, shift to a non-capturing mode upon receiving an instruction representing a suspension of the radiographic imaging, shift to a capturing mode upon receiving an instruction representing a start of the radiographic imaging, and drive, in the capturing mode, the image capturing device using a synchronization signal (SYNC) as the trigger, the synchronization signal (SYNC) being for a synchronous controlling between the operation and the radiation irradiation repeated at the period, characterized in that, the controller comprises a signal generator configured to generate another signal (SYNCX) differing from the synchronization signal (SYNC) when the controller is in the non-capturing mode, and the controller, in the non-capturing mode, is configured to drive the image capturing device using the other signal (SYNCX) as the trigger instead of using the synchronization signal (SYNC), thereby suppressing lowering of a temperature of the sensor array in the non-capturing mode from the temperature of the sensor array in the capturing mode, to prevent power consumption of the image capturing device from lowering.