1. A radio propagation estimating method of estimating a radio propagation path from a transmitting point of a radio wave to a receiving point, said method comprising: an acceptance step that accepts a position of the transmitting point and a position of the receiving point; an object surface acquisition step that acquires data on object surfaces that may affect the radio wave from the transmitting point; a receiving area setting step that sets a predetermined-size receiving area that includes the receiving point; a ray launching method-based path estimation step that estimates, via a ray launching method, radio propagation paths from the transmitting point to the receiving area using the object surfaces whose data is acquired in said object surface acquisition step; an object surface extraction step that extracts object surfaces, existing in the radio propagation paths estimated by the ray launching method, from the object surfaces acquired by said object surface acquisition step; and an imaging method-based path estimation step that estimates, via an imaging method, a radio propagation path from the transmitting point to the receiving point using only the object surfaces, extracted by said object surface extraction step, as object surfaces on which the radio wave is reflected and which change a direction of the path.