A mobile communication method according to the present invention includes step of determining to change a manager of a radio base station from a first network device to a second network device, step of notifying the first network device and the second network device of the determination result, step of transmitting a reset request to the radio base station, step of performing reset operation by the radio base station, step of notifying the radio base station of address information of the second network device and step of connecting to the second network device by the radio base station using the notified address information.