The invention provides an aerial photogrammetry by using two or more of flying vehicles each equipped with a GPS device and an image pickup unit, comprising a step of setting up two or more photographing points and of setting up a photographing point area respectively with each of the photographing points as the center, a step of measuring a position of the flying vehicle by said GPS device, a step where each of the flying vehicle reaches each corresponding photographing point area and maintains the position of the photographing point area, a step of acquiring a time when the flying vehicle finally reaches the photographing point area, a step of setting up a shutter timing time after a predetermined time from the moment when the flying vehicle has finally reached the photographing point area, and a step of taking aerial photographs by the two or more flying vehicles at the shutter timing time.
