A method and an apparatus for determining a protocol data unit (PDU) session service network element to control an aggregated maximum bit rate (AMBR), where the method includes receiving, by a control plane function network element, a request for establishing a first PDU session from a mobility management device, where the request for establishing the first PDU session includes a first data network name (DNN), determining, by the control plane function network element, that a same control plane function network element and a same user plane function network element need to be selected for a PDU session corresponding to the first DNN, and sending, by the control plane function network element, first indication information to the mobility management device, where the first indication information is used to indicate that a same control plane function network element needs to be selected for the PDU session corresponding to the first DNN.