The B6-hSCN9A mouse is a mouse Scn9a humanized model, generated by replacing the mouse Scn9a gene (including the 5' UTR and 3' UTR) with the corresponding human SCN9A gene sequence using gene editing technology. This model can be used for studying the pathogenic mechanisms of neurological diseases such as erythromelalgia, Dravet syndrome, small fiber neuropathy, and congenital insensitivity to pain, as well as for screening analgesic drug candidates.