The paper discusses the identity of the academia-defined Nan-shih Amis by exploring the relationship among the named residents and villages, the geography of social activities and spatial cognition of those outsiders who named in various historical stages. In addition to investigating the origin and development of the term Nan-shih Amis, attention is given to how those people being collectively termed Tit-kha-soan, Sonkau, Ki-lai and Lam-sek (i.e., Nan-shih) through history and the explanation is based on the spatial cognition of the labelers. Moreover, the paper also presents the inquiries into the homogeneity of cultural elements of Nan-shih Amis, as well as the construction and interpretation of their own identity by the associated descends.