A radio base station apparatus includes a plurality of call processing controllers for call processing control, a supervision controller supervising the call processing controllers, and a system data memory storing system data necessary for restarting. Each call processing controller includes a plurality of function portions and a memory storing data necessary for restarting. One function portion in one call processing controller includes a reset type recorder recording either an overall radio base station reset, one call processing controller reset only, or one function portion reset in the one call processing controller. Depending on the above recorded reset type, the one function portion initiates by reading data necessary for restarting from the system data memory or the memory in the one call processing controller.