To provide a method for estimating a radio communication line in a radio communication system capable of more simply estimating the radio transmission line.

A method for estimating the transmission line estimating a state of the transmission line between a transmitting station and a receiving station in the radio communication system comprises the steps of transmitting a predetermined signal from the transmitting station to the receiving station, obtaining a receiving level of the signal with a level of the predetermined signal from the transmitting station as a reference when the signal corresponding to the predetermined signal is received at the receiving station, obtaining a delay time of receiving timing of the signal in the receiving station to transmitting timing of the predetermined signal in the transmitting station, and generating estimating information representing the state of the transmission line between the transmitting station and the receiving station by using the receiving level and delay time of the signal received at the receiving station obtained as described above.