To provide a demultiplexer for a digital broadcast receiver for demultiplexing a multiplexed broadcast channel signal, and demultiplexing method.

In a demultiplexer for a digital broadcast receiver, a PID filter extracts broadcast streams corresponding to multiplex broadcast channels from an inputted digital broadcast stream and outputs digital broadcast streams of a plurality of broadcast channels. Thus, in the digital broadcast streams of the multiplex broadcast channels, a corresponding word is outputted from a FIFO memory and stored in a CA buffer by a grant signal of an arbiter that arbitrates bus occupancy by the CA buffer. In the CA buffer, the corresponding word is stored in a packet unit while including a control word, and a packet that is arbitrated by the arbiter and outputted from the CA buffer to a CA module is descrambled and then outputted in a viewable form via a decoder.