The invention provides a network slice configuration method, a network slice configuration device, a radio access network RAN node and a terminal, wherein the method comprises the steps of: sending basic slice configuration information to the terminal, so that the terminal reports pre-configured network slice selection assisted information used for network slice selection; and, according to the network slice selection assisted information, sending a target message to the terminal, so that the terminal determines a target RAN slice in multiple alternative RAN slices corresponding to each supported core network CN slice according to the target message. By means of the network slice configuration method, the network slice configuration device, the radio access network RAN node and the terminal provided by the invention, multiple CN slices are mapped to an RAN slice, so that one RAN node can support a lot of CN slices; therefore, the radio resources of the RAN node can be saved; and furthermore, the processing capability of the RAN node can be improved.