A radiographic imaging device including: a sensor portion that generates an output signal according to an irradiated amount of irradiated radiation； a detector that based on the output signal detects a radiation irradiation start of radiation irradiated from a radiation source during capture of a radiographic image； a noise data generation means that, based on an output signal from the sensor portion in a non-irradiation state of radiation from the radiation source, generates noise data relating to noise incorporated in the output signal； a controller that controls detection sensitivity to radiation irradiation start in the detector according to a degree of variation in noise level expressed by the noise data； and an imaging unit that captures the radiographic image after radiation irradiation start has been detected by the detector.
