Performance analysis of ZigBee based real time Home Automation system Incorporation of wireless technology in Automation system has led to the development of remote monitoring and controlling of loads. It is essential to select and implement an appropriate technology according to the desired application area. This paper describes the various factors viz. network topology, network span and transmission time, which influence the performance of the system. It also illustrates ZigBee (over IEEE 802.15.4) based Home Automation system (HAS), for remote controlling and monitoring of loads/appliances. In order to estimate the total power consumption of the desired load, the designed HAS can be operated in either of the two modes viz. Energy measurement IC `CS5490′ based mode and Current sensor IC `WCS 2705′ based mode. It provides real time power monitoring with the help of a PC-based GUI application developed on Net Beans Java platform. Further, the paper emphasizes on performance evaluation of the system by analyzing the various performance metrics viz. the Latency, Round Trip Delay (RTD) time and Received Signal Strength Indicator (RSSI).