A curriculum is a form of politics (Apple, 1993). The politics of a curriculum defines what is legitimate and valued and what is not. In Taiwan, the objectives of vocational high school (VHS) education are to prepare students to acquire relevant professional knowledge and practical skills and to integrate them into their future career development. However, with the push for students to pass the Joint Entrance Examination (JEE), few English curriculum designs have been developed to align with the originally intended objectives. Inspired by the notion of critical pedagogy and participatory curricula, a task-based ESP (English for Specific Purposes) program was developed for a group of Vocational High School (VHS) students. This program aimed to empower and embody an alternative curriculum politics that opposed the test-oriented curriculum but highlighted authentic language use and meaningful tasks and emphasized the integration of theory and practice. This paper analyzes and describes how an alternative curriculum politics was shaping and being shaped by different components of the ESP program based on the language design model proposed by Nation and Macalister (2010). It also demonstrates how instructional objectives, activities, and materials were organized and implemented in the four courses of the ESP program to reflect the curriculum politics. Finally, to deepen and broaden our understanding of the notion of curriculum politics, this study reconceptualizes curriculum politics by comparing and contrasting the sociocultural system of the ESP program and that of the VHS English education based on the six dimensions of Gee‘s (1999) cultural model. In light of the findings and discussion, both theoretical and practical implications are addressed. Suggestions for further studies are provided.