The invention discloses a wireless communication system and method and a method for transmitting the pilot frequency in the wireless communication system. The method for transmitting the pilot frequency comprises the following step: a base station transmits the pilot frequency to a terminal in the broadcasting service region and/or multicast service region of a downlink subframe, wherein the pilot frequency of the downlink subframe satisfies the following condition: in each physical resource block of the downlink subframe, the number of pilot frequencies corresponding to each data stream is a natural number between 6 to 11. By using the wireless communication system and method of the invention, the pilot density of the radio frequency can be increased so as to increase the quality of the channel estimation and improve the overall performance of the system. Therefore, the wireless communication system and method of the invention can satisfy the needs of the broadcasting service.