A communication control method executed by a communication system including: a slice selection device that retains slice correspondence information including information in which a slice serving as a virtual network logically generated in a network infrastructure, a processing server corresponding to the slice, and a service to be used by a terminal are associated with one another and selects a slice based on the slice correspondence information, and a plurality of processing servers that execute processing related to the terminal while each processing server of the plurality of processing servers is associated with one or more slices, the communication control method comprising: a step in which one processing server having received a request for use of a service from the terminal transfers the request for use to the slice selection device; a step in which the slice selection device selects a slice corresponding to a service related to the request for use and a target processing server corresponding to the slice based on the slice correspondence information and notifies the one processing server of selection result information including information related to the slice and the target processing server which have been selected; a step in which the one processing server determines whether or not the one processing server is the target processing server based on the information related to the target processing server included in the selection result information, and responsive to a determination that the one processing server is the target processing server, the one processing server performs processing for a service related to the request for use, and responsive to a determination that the one processing server is not the target processing server, the one processing server transfers a request for processing for a service related to the request for use, to the target processing server; and a step in which the slice selection device or the one processing server queries a user data manager which manages information related to a terminal user regarding whether or not the terminal is capable of using the selected slice. a step in which one processing server having received a request for use of a service from the terminal transfers the request for use to the slice selection device; a step in which the slice selection device selects a slice corresponding to a service related to the request for use and a target processing server corresponding to the slice based on the slice correspondence information and notifies the one processing server of selection result information including information related to the slice and the target processing server which have been selected; a step in which the one processing server determines whether or not the one processing server is the target processing server based on the information related to the target processing server included in the selection result information, and responsive to a determination that the one processing server is the target processing server, the one processing server performs processing for a service related to the request for use, and responsive to a determination that the one processing server is not the target processing server, the one processing server transfers a request for processing for a service related to the request for use, to the target processing server; and a step in which the slice selection device or the one processing server queries a user data manager which manages information related to a terminal user regarding whether or not the terminal is capable of using the selected slice.