A PET communications system based on an IP and a CAN bus comprises: a control and display module, and at least one group of device access modules that communicate with and are connected to the control and display module based on an IP. The device access modules comprise a transfer unit and a client unit. The transfer unit communicates with and is connected to the control and display module based on an IP network. A network interface communications module is newly added in the transfer unit. The client unit comprises at least one group of detector control assemblies. Each group of detector control assemblies comprises a detector control board. The detector control board comprises a first processor and a first peripheral circuit disposed to cooperate with the first processor. The first processor is correspondingly integrally provided with a network interface communications module, so that each group of detector control assemblies communicates and is connected to the transfer unit based on the CAN bus. The system uses a communications architecture based on an IP and a CAN bus, and comprehensively uses advantages of IP communication and a CAN protocol, which reduces hardware costs of the system, reduces a software development time, and improves a response time of the system, so that the reliability is high.Linvention concerne un système de communication PET sur la base dIP et de bus CAN, qui comprend : un module de commande et daffichage, et au moins un groupe de modules daccès de dispositif qui communiquent avec le module de commande et daffichage et sont reliés à celui-ci sur la base dIP. Les modules daccès de dispositif comprennent une unité de transfert et une unité client. Lunité de transfert communique avec le module de commande et daffichage et est reliée à celui-ci sur la base dun réseau IP. Un module de communication dinterface réseau est nouvellement ajouté dans lunité de transfert. Lunité client comprend au moins un groupe densembles de commande de détecteur.
