A multiplexing system (10) is provided which includes a plurality of encoders (12-15) which generates elementary streams, respectively, CPU (16), multiplexer (17), instruction memory (18), and a data memory (19) which stores a plurality of elementary data to be multiplexed. Each of the encoders (12-15) divides elementary data into units, and stores the data into the data memory (19). The CPU (16) generates, for each of the data units, instruction data having stated therein a storage location in the data memory (19) and stores the instruction data into the instruction memory (18). The multiplexer (17) reads the instruction data one by one from the instruction memory (18), and reads data units stated in the instruction data sequentially from the data memory (19), for generation of a multiplexed stream. Thus, the burden of processing to the controller can be lessened.