This thesis critically examines the language ideologies underpinning the language curriculum and language teaching practices in a nihonjingakkō, a full-time day school for children of Japanese expatriates, in Belgium. By drawing on the theoretical frame of ideology of authenticity and ideology of anonymity (Woolard, 2016), I investigate what language ideologies the school, principal, and language teachers hold and how these influence the school’s language curriculum and language teachers’ pedagogy. The research adopted an ethnographically-oriented case study approach. The data consisted of semi-structured interviews with the principal and language teachers along with questionnaires, classroom observations, and analysis of policy documents from the school. Using qualitative content analysis, the study illustrated the complexity and multiplicity of language ideologies manifested in the school’s policy and practice. The findings indicate that the language ideologies operating in the school influencing the language curriculum and pedagogy are primarily monolingual and homogeneous, and largely influenced by the dominant language ideologies of Japan’s Ministry of Education and Japanese society. Consequently, the school positions itself as if it were a mainstream school in Japan despite its location in the multilingual setting of Belgium. This was manifested through Japanese and English occupying the dominant role in the language curriculum, while French was marginalized, and no other languages were offered. Furthermore, a monolingual approach to pedagogy was adopted that emphasized keeping language separate, disregarding students’ and language teachers’ rich multilingual repertoire. The idea of developing students to be multilingual speakers is missing from the school curriculum and pedagogy, since the school do not conceive their multilingual abilities as a resource. In conclusion, this study proposes a critique of the language education policy of the nihonjingakkō operated in non-Anglophone settings such as Belgium. ...