In order to control sub-processors in parallel without losing extensibility, an execution control circuit (30), which forms a multi-processor system (1), issues a process command (CMD) to each of sub-processors (20—1 to 20—3) based on a process sequence (SEQ) designated by a main processor (10), and acquires a process status (STS) which indicates an execution result of processing executed by each of the sub-processors (20—1 to 20—3) in accordance with the process command (CMD). An arbiter circuit (40) arbitrates transfer of the process command (CMD) and the process status (STS) between the execution control circuit (30) and each of the sub-processors (20—1 to 20—3).