Disclosed is a method for network charging, which includes: a data center management network element, upon reception of a charging resource request message from a controller, supports a charging function of a processing network element by a virtual machine and feeding back information of the processing network element to the controller; the data center management network element sending charging strategy information, user state information and information of UGW to the processing network element, which implements transmission of a traffic flow with the UGW according to the information of UGW, charges for the traffic flow according to the charging strategy information and the user state information, and feeds back charging processing information to the data center management network element; and the data center management network element feeding back the charging processing information to the controller. The disclosure further provides a data center, controller, UGW and system for network charging. Thus the charging service may be implemented for a SDN EPC network.