PROBLEM TO BE SOLVED: To provide a medical image processing device and an X-ray diagnostic device that enable a blood flow to be grasped accurately.SOLUTION: A medical image processing device includes an acquisition function and a correction function. The acquisition function acquires the transition with time in signal strength of each pixel in a plurality of X-ray images collected in a time-series manner using a contrast medium. Based on the signal strength of signals adjacent in a time-series manner in the transition with time in the signal strength, the correction function corrects the transition with time in the signal strength so as to exclude a value of the signal strength of a deviating signal having a value deviating from the value of the signal strength of the adjacent signals.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2017,JPO&INPIT【課題】血流を正確に把握することを可能にする医用画像処理装置及びX線診断装置を提供すること。【解決手段】実施形態の医用画像処理装置は、取得機能と、補正機能とを備える。取得機能は、造影剤を用いて経時的に収集された複数のX線画像における画素ごとの信号強度の経時的な遷移を取得する。補正機能は、信号強度の経時的な遷移において時系列的に隣接する信号の信号強度に基づいて、隣接する信号の信号強度の値と乖離する値を有する乖離信号の信号強度の値を除くように、信号強度の経時的な遷移を補正する。【選択図】図1