A positioning support apparatus includes a hardware processor. The hardware processor obtains a radiographic image of a subject taken through a radiography. Based on the obtained radiographic image, the hardware processor detects a relative positional relationship between the subject and at least one of a radiation detector and a radiation source, the positional relationship being at a time when the radiographic image is taken. The hardware processor receives a change input for simulating a change of a position of the at least one of the radiation detector and the radiation source. Based on the detected positional relationship and the received change input, the hardware processor generates a simulation-reflected image that is an image of the subject reflecting the change of the position of the at least one of the radiation detector and the radiation source. The hardware processor outputs the generated simulation-reflected image.
