The implementation of school-based curriculum development has caused great impact on the existing power structure and cultural ecology at schools. From a critical sociological perspective, this article examines the hidden issues involved in school-based curriculum development, such as shifting power in curricular decision making, restructuring power relations, and organizational reculturing. In this article, by analyzing the power structure at schools, the authors first explore the school functions after the shifting of power in curriculum decision making. Then, by analyzing the school culture, the authors go further to examine the possible changes of organizational culture and power relations that might occur in the implementation of school-based curriculum development. Finally, based on the analysis of two cases, the authors deconstruct the issues of power exercise and the changes of teacher culture behind school-based curriculum development to highlight the impact that the practice of school-based curriculum development may bring to power structure and cultural ecology at schools.