This radiographic image processing device (100) has a brightness of a radiographic image (Xnogrid) including a signal of scattered radiation, which is imaged by the radiation applied to the subject (S) in a state where the grid (8) is not arranged. An adjustment coefficient (Iideal / Ireal) for adjusting the signal reduction rate (Dscat) by removing the scattered component in the subject (S) of the radiation transmitted through the subject (S) acquired based on the value (Inogrid) is calculated. An image processing operation unit (6) is provided.この放射線画像処理装置(100)は、グリッド(8)が配置されていない状態において被検体(S)に照射された放射線により撮像される、散乱線の信号が含まれる放射線画像(Xnogrid)の輝度値(Inogrid)に基づいて取得される被検体(S)を透過する放射線の被検体(S)における散乱成分を取り除くことによる信号低下率(Dscat)を調整する調整係数(Iideal/Ireal)を算出する画像処理演算部(6)を設ける