Rapid advances in information technology and telecommunications, and more specifically wireless and mobile communications are leading to the emergence of a new type of information infrastructure that has the potential of supporting an array of advanced services for healthcare. This paper developed a wireless biomedical sensor network prototype system based on ISM band for healthcare. It offers flexibility and mobility to save cost and energy spent on wiring. The framework hardware and software structure, related programming, the accuracy of the system and an optimization of power consumption are also discussed in this paper. Comparing the system which uses ISM band with traditional wired network system for healthcare, it has advantage of low cost, low power and wider coverage.