As in other parts of the world, private tutoring has expanded significantly in Mainland China during the past decade. This has been driven by factors including dramatic economic growth, high-stakes examinations, and the traditions of a Confucian culture at the macro-level, and school leadership and family incomes, at the micro-level. This paper examines the demand for private supplementary tutoring in Chongqing, China. It is based on a mixed-methods study of tutoring received by Grade 9 students. Based on an overview of the demand for shadow education by the sampled students and the driving factors at multiple levels, this paper investigates the role of teachers' power in shaping the demand. It draws on the data obtained from interviews and case studies, applying the theory of power bases to map the power relations among various stakeholders in both mainstream and shadow education systems. The study reveals that nearly half of Grade 9 students receive private tutoring, with mainstream teachers as the most popular category of tutors. While some dimensions of this extra work for teachers may be laudable, other aspects could be described as forms of corruption. This highlights the need to examine the power of teachers. The paper contributes to research in a wider context by refining understanding of the nature of shadow education from a Chinese perspective. It addresses the gap in empirical research on Chinese teachers' involvement in shadow education through the lens of power relations.