When the global budget system carried out, cost control and resource allocation become the important considerations for the hospital operation. This research analyzes the effect of the physicians' professionalism on the clinic decisions through the use of AIS. The use of AIS is investigated by two dimensions: the use of the broad-scope management accounting information and the use of interactive management accounting system. This research uses both quantitative and qualitative research methodologies, and the results indicate that physicians' professionalism have a negative relationship with their clinical decision making controlled through global budget. However, the clinical decision making will be controlled via the use of broad-scope management accounting information and the use of interactive management accounting system. It reveals that physician professionalism will affect their use of management accounting system, and further influence their clinical decision making.