A radiographic apparatus includes: a plurality of detection elements arranged in a two-dimensional fashion at least one radiation sensor configured to change a signal value to be output, when radiation is emitted thereto and an irradiation start detecting unit configured to determine whether X-ray emission from an X-ray generator has been started based on the signal value output from the radiation sensor, wherein, when the signal value output from the radiation sensor moves out of a predetermined range, the irradiation start detecting unit does not determine whether the signal value output from the radiation sensor is a signal value outside the predetermined range at least, and when the number of times the signal value output from the radiation sensor moves out of the predetermined range reaches a predetermined number, the irradiation start detecting unit detects a start of X-ray emission from the X-ray generator.
