A dynamic image processing apparatus includes: a hardware processor that: extracts a lung-field region from at least one of a plurality of frame images of a chest dynamic image obtained by radiographing a dynamic state of a chest of an examinee; sets a feature point in a position that moves according to a movement of a lung field due to respiration in the lung-field region extracted by the hardware processor; searches a frame image other than a frame image in which the feature point has been set for a corresponding point that corresponds to the feature point set by the hardware processor, and estimates a correspondence relationship of each pixel in the lung-field region among the plurality of frame images in accordance with a positional relationship between the feature point set by the hardware processor and the corresponding point searched for by the hardware processor.