To provide a bus management device that can maximally use a data transfer band of a bus and limit accesses between the devices as required.

An access permission information storage section stores access permission information between the devices. A packet analysis section captures a packet delivered through the bus to extract transmission source device information and transmission destination device information of the packet. An access discrimination section discriminates the propriety of the access on the basis of the access permission information stored in the access permission information storage section and the transmission source device information and the transmission destination device information extracted by the packet analysis section. When the access discrimination section discriminates that the access is not allowed, a packet transmission section transmits a disapproval command to the transmission source device and transmits an invalid command to the transmission destination device.