A method for establishing message priority in network slices based on quality of service (QoS) parameters includes receiving, by a network slice configuration service provider entity and from a network slice management service provider entity, a network slice creation notification message containing at least a QoS profile corresponding to a created network slice, utilizing the QoS profile to derive a service based interface (SBI) message priority (SMP) associated with the network slice, and providing the SMP to a requesting access and mobility management function (AMF) entity in response to receiving a network slice selection request message from the AMF entity, wherein the AMF entity assigns the SMP level value to network traffic directed to the network slice.