A policing device having a table storing monitored bandwidth, packet history information for each importance level, and the allocation weight of the monitored bandwidth for each importance level, a policing table control circuit for reading out these items of information into each storage of a policing unit when a packet is inputted, and a calculation unit for judging the bandwidth of the input packet as being conformant or non-conformant to the contract on the basis of these items of information, thereby to control the bandwidth at each importance level.