Reliability Evaluation of WSN is an currently the booming topic in the communication networking environment which has a drastic advantage over the traditional method and has to be adopted in the industrial environment for the mile connections in networking .The WSN is also an alarming need in the communication network to transport, chunks of data that are forwarded in node to node form in most of the application in the day to day life that has an outrageous development in the present world in the field of networking, which has adaptive link control and enhanced hop-by-hop reliability. The WSN has thousands of sensor points which enable the evaluation of permanent faults, optimize the fault occurrences (by improving the WSN QoS), sensor fusion,collaborative target tracking, along with this the Zigbee based networking solution is rapidly rising as one of the best choices in order to provide the reliable WSN environment among the variety of sensor network applications. . On this aspect, this paper aims to discuss the technology to evaluate the reliability of sensor network