To provide a radio base station apparatus capable of preforming processing corresponding to internal delay even when the internal delay occurs.

When a message is received whose performance timing (CFN=100) is designated from a radio network controller 130, the radio base station apparatus 120 converts a timing value designated in the reception message into another timing value (SFN=356) with a larger period through the use of a CP card 310 or a BB card 350, and transmits the message to a low-order function part (DSP 410) in the BB card 350 at the timing. The DSP 410 compares the actual timing of arrival of the message with the timing which is indicated from a high-order device with a parameter, so as to determine whether the message normally arrives or arrives after the indicated timing due to the internal delay. Then the corresponding processing is performed based on the determined arrival timing.