According to one implementation, a thoracic diagnosis assistance information generation method includes the following. A dynamic state of a chest portion is captured to generate frame images. Air velocity is calculated by dividing a lung field region extracted from one frame region into small regions, corresponding the small regions among the frame images, and calculating a feature amount showing air velocity. Air velocity distribution is calculated by dividing the lung field region into block regions in a trunk axis direction, calculating a feature amount showing air velocity of each block region based on a feature amount showing the air velocity of the small regions in the divided block regions, and calculating a feature amount showing air velocity distribution of the lung field region based on the calculated feature amount showing the air velocity of each block region.
