PROBLEM TO BE SOLVED: To provide a mechanism for suppressing the deterioration of radiation detection capability when performing non-synchronous imaging.SOLUTION: A radiation imaging device includes: an imaging part 2010 for detecting a radiation ray that transmits a subject, and taking a radiation image based on the radiation ray a measurement circuit 2041 for measuring a time elapsed from the time the imaging part 2010 starts stand-by of radiation ray detection an acquisition circuit 2011 for acquiring parameters related to imaging processing by the imaging part 2010 an estimation circuit 2042 for estimating an amount of change in the radiation detection capability based on time characteristic data 2022 of the radiation detection capability stored in a storage part 2020, the parameters acquired by the acquisition circuit 2011, and the time elapsed measured by the measurement circuit 2041 and determination circuits 2043 for determining whether or not to reset the stand-by state of the radiation ray detection by the imaging part 2010 based on the amount of change in the radiation detection capability estimated by the estimation circuit 2042 and a threshold 2021 of the radiation detection capability stored in the storage part 2020.
