The utility model provides a mathematics modeling system based on petri net, modeling system connects gradually including input device, central processing unit and display device, input device, central processing unit and display device, central processing unit is including the petri module and the CPU that are used for establishhing petri wire mould type, and the petri module is connected with CPU. Petri module through being used for setting up petri wire mould type is connected with the CPU hot plug, can make a plurality of petri wire mould types that are applicable to different aspects use in advance, when needing to be changed the petri module, direct with the module from CPU extract can, very the petri net of convenient and fast's the different function use of realization is built pattern.