A target image to be corrected is generated by arranging partial images acquired by scanning a tissue of a living body with light and temporally continuously receiving the light from the tissue. A processor of a medical image processing device performs detecting position shift amounts, acquiring a component, and correcting. In the process of detecting position shift amounts, the processor detects the position shift amounts between the partial images (S3). In the process of acquiring, the processor acquires an assumed result of at least one of a component in the position shift amount caused by movement of the tissue, and a component in the position shift amount caused by a shape of the tissue (S4). In the process of correcting, the processor corrects a position of each of the partial images based on the component in the position shift amount (S7).