Provided is a casino game medium and a game table system capable of reducing adjacent reading without limiting a design of a game table. The casino game medium 100 includes the medium side antenna 110, the resistance element 111 connected to the medium side antenna 110, and the IC chip 112 that stores medium information and outputs the medium information based upon an induced electromotive force generated in the medium side antenna 110. The medium side antenna 110 is designed so that the resonance frequency thereof is higher than the specified frequency band.