Methods, systems, and computer readable media for validating a session management function (SMF) registration request are disclosed. One method occurs at a network node. The method comprises: receiving, from a first SMF in a home network, a registration request indicating a first network identifier identifying a visited network where a user device is roaming; determining whether the registration request is valid by comparing the first network identifier and a second network identifier associated with an access and mobility management function (AMF) serving the user device; and performing at least one action based on the determining.