An antenna module which transmits and receives a radio signal via a wireless network, the antenna module includes an antenna configured to transmit and receive the radio signal, a circuit configured to convert a signal received from outside into a radio signal, make the antenna transmit the converted radio signal, and transmit a signal generated by processing the radio signal received by the antenna to the outside, a tubular casing configured to accommodate the circuit to cover a periphery of the circuit, an antenna accommodator provided at one end of the casing and configured to accommodate the antenna to allow the antenna to transmit and receive the radio signal, a connector joined to the casing and connectable to an external device which transmits and receives a signal to and from the circuit, a router configured to relay the signal processed by the circuit, and a gateway configured to communicatively connect the router and the external device connected to the connector.