An emergency notification in-vehicle terminal mountable to a vehicle is disclosed. The in-vehicle terminal is configured to transmit emergency information to a center in response to detection of an occurrence of an emergency situation involving the vehicle. The in-vehicle terminal determines, in response to the detection of the occurrence of the emergency situation, whether the emergency notification in-vehicle terminal is operating by an electric power of a back-up battery. If it is determined that the emergency notification in-vehicle terminal is operating by the electric power of the back-up battery, the in-vehicle terminal transmits a minimum necessary amount of the emergency information to the center.