An ordinary telephone communication circuit is provided in addition to the emergency informing circuit in an emergency informing apparatus. In the non-emergency condition, ordinary telephone communication is provided through a wireless communication network. In the emergency condition, the emergency data is transmitted to a predetermined station through the wireless communication network. An interface for transmitting and receiving data is further provided. A data converter for converting data may be provided as a data communication adapter. An automatic dialing circuit may be provided. An emergency informing system including the emergency informing apparatus, the wireless network, and a terminal of a predetermined station for receiving the emergency data from the emergency informing apparatus is also disclosed.