This study focuses on the transitions in the structure of elementary school language curriculum through literature review. The time span of the analysis covers 1949 to present. In sum, the development of language curriculum can be divided into the following periods: the stable period (1949-1970), the mandatory period (1971-1986), and the open period (1987 to present). In these periods, Taiwan's elementary school curriculum has shifted from Mandarin-only policy towards greater emphasis on dialects and foreign languages. The underlying forces that have contributed to these transitions are analyzed. The transitions of language curriculum in Taiwan demonstrate how main-stream language helped establish the legitimacy and stability of the state, how mono-language constituted a hegemonic culture and turned other languages or dialects into marginal, and lower status. Implications and issues for future language curriculum policy are also discussed.