To provide a radio communication system and apparatus capable of promptly and automatically recovering communication in the case where a radio wave failure occurs.

The radio communication system is provided which is comprised of a master station and a slave station. The master station includes a transmitting/receiving section for transmitting a polling request at an initial frequency to the slave station and receiving a response to the polling request from the slave station. The slave station includes: a transmitting/receiving section for receiving a polling request from the master station and transmitting a response to the polling request to the master station; a failure detecting section for detecting whether or not any failure occurs in communication at the initial frequency with the master station; a frequency selecting section for selecting a substitutive frequency to be used as a substitution of the initial frequency from among a plurality of frequencies including the initial frequency in the case where the occurrence of any failure is detected by the failure detecting section; and a frequency notifying section for notifying the master station about that the communication should be performed at the substitutive frequency selected by the frequency selecting section.