A multimedia signal processing apparatus comprises communication service units having a plurality of types of signal processing modes corresponding to a plurality of types of communication service classifications, a communication service classification identifying unit for identifying, on the basis of signal processing request information on one call communicated from a higher-rank node, a communication service classification for that call, and a mode control unit for controlling a signal processing mode of the communication service unit to a mode suitable for the communication service classification identified in the communication service classification identifying unit. With this configuration, in the multimedia signal processing apparatus, the signal processing mode of the communication service unit is controlled to a mode suitable for the service classification for each call, which can considerably decrease the number of communication service units to be mounted and significantly reduce the probability of the rejection of newly arrived call.