A network slice determining method, comprising: obtaining , by a network selection function, NSF, node, an identity of a terminal; sending , by the NSF node, the terminal identity to a home subscriber server, HSS; receiving, by the NSF node, a slice identifier of a network slice that is sent by the HSS, wherein the slice identifier is determined by the HSS based on the terminal identity; and determining, by the NSF node based on the slice identifier, the network slice to which the terminal belongs, wherein the NSF node stores a correspondence between the slice identifier of the network slice and network slice attribute information, and wherein the network slice attribute information comprises at least one of a terminal type, a service type, and a location range that are supported by a network slice corresponding to the network slice attribute information; and the determining, by the NSF node based on the slice identifier, the network slice to which the terminal belongs comprises: querying , by the NSF node based on the slice identifier of the network slice network slice attribute information corresponding to the slice identifier; obtaining , by the NSF node, assistance information from the terminal, wherein the assistance information comprises at least one of a terminal type of the terminal, a service type requested by the terminal, and location information of the terminal; and if the assistance information matches the network slice attribute information, determining , by the NSF node, a network slice indicated by the slice identifier as the network slice to which the terminal belongs. obtaining , by a network selection function, NSF, node, an identity of a terminal; sending , by the NSF node, the terminal identity to a home subscriber server, HSS; receiving, by the NSF node, a slice identifier of a network slice that is sent by the HSS, wherein the slice identifier is determined by the HSS based on the terminal identity; and determining, by the NSF node based on the slice identifier, the network slice to which the terminal belongs, wherein the NSF node stores a correspondence between the slice identifier of the network slice and network slice attribute information, and wherein the network slice attribute information comprises at least one of a terminal type, a service type, and a location range that are supported by a network slice corresponding to the network slice attribute information; and the determining, by the NSF node based on the slice identifier, the network slice to which the terminal belongs comprises: querying , by the NSF node based on the slice identifier of the network slice network slice attribute information corresponding to the slice identifier; obtaining , by the NSF node, assistance information from the terminal, wherein the assistance information comprises at least one of a terminal type of the terminal, a service type requested by the terminal, and location information of the terminal; and if the assistance information matches the network slice attribute information, determining , by the NSF node, a network slice indicated by the slice identifier as the network slice to which the terminal belongs. querying , by the NSF node based on the slice identifier of the network slice network slice attribute information corresponding to the slice identifier; obtaining , by the NSF node, assistance information from the terminal, wherein the assistance information comprises at least one of a terminal type of the terminal, a service type requested by the terminal, and location information of the terminal; and if the assistance information matches the network slice attribute information, determining , by the NSF node, a network slice indicated by the slice identifier as the network slice to which the terminal belongs. <EOS>