To provide a radiation detector with which it is possible to suppress the effect of discontinuous deflection even when a flexible base material is used for a sensor substrate, and a radiographic imaging device.SOLUTION: A radiation detector 10 comprises: a sensor substrate 12 including a flexible base material 14 and a layer provided on a first surface 14A of the base material 14 and having a plurality of pixels 16 formed therein for accumulating electric charges generated in accordance with light converted from radiation； a conversion layer 30 for converting radiation into light and provided on the first surface 14A side of the sensor substrate 12； and a protective film 32 covering a range from the side of the conversion layer 30 that is opposite the side on which the sensor substrate 12 is provided to a position of a second surface 14B opposite from the first surface 14A of the base material 14 that is opposite a position of the first surface 14A at an end of the conversion layer 30.SELECTED DRAWING: Figure 3【課題】センサ基板に可撓性の基材を用いた場合であっても、不連続な撓みの影響を抑制することができる放射線検出器及び放射線画像撮影装置を提供する。【解決手段】放射線検出器１０は、可撓性の基材１４、及び基材１４の第１の面１４Ａに設けられ、かつ放射線から変換された光に応じて発生した電荷を蓄積する複数の画素１６が形成された層を含むセンサ基板１２と、センサ基板１２の第１の面１４Ａの側に設けられ、かつ放射線を光に変換する変換層３０と、変換層３０における、センサ基板１２が設けられた側の反対側の面から、基材１４の第１の面１４Ａとは反対側の第２の面１４Ｂの、第１の面１４Ａにおける変換層３０の端部の位置とは反対側の位置までを覆う保護膜３２と、を備える。【選択図】図３
