Wireless Sensor Network (WSN) can be effectively used for continuous monitoring of patient in hospitals and in homes for elderly and baby care. For this the medical data in terms of vital body parameters of patient are to be collected. Various bio sensors such as temperature, heart rate and pulse rate are attached to the body of patient and data is collected and send via wireless sensor network. The efficacy of healthcare monitoring system depends on ease of operations and how efficient and accurate the data communication is. Many parameters are available to evaluate the performance of healthcare system based on WSN. This paper aims to study the performance metrics available and evaluate the performance of the system based on certain WSN metrics such as LQI, Packet delivery ratio, network throughput etc.