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In the industrial automation, Industrial Wireless Sensor Networks (IWSNs) have been increasingly applied due to a great number of benefits such as convenient installation, flexible deployment and cost efficiency. Compared with conventional wireless systems, IWSNs have more stringent requirements communication reliability and real time performance. However, IWSNs are frequently deployed in a hash industrial environment with electromagnetic disturbances, moving objects and non-line-of-sight (NLOS) communication. Because of the vulnerability of wireless signal, IWSNs are under high risk oftransmission failures, which may result in missing or delaying of process orcontrol data. For industrial automation, missing the process or control deadlineis intolerable, which may terminate industrial application and finally result in economic loss and safety problems. From hierarchy point of view, the high communication reliability and low communication latency can be achieved from different network layers. OnMAC layer, existing protocols in IWSNs only provide automatic repeat request (ARQ) to improve reliability at the cost of real time performance. Analternative method is to apply Forward Error Correction (FEC) mechanism on MAC layer to provide more reliable transmissions and reduce acknowledgement messages by recovering error data. On network layer, routing protocolplays an important role in both communication reliability and latency. Traditionalrouting protocols in IWSNs are either hardly able to fulfill both of these requirements or overcomplicated.In this thesis, we initially explore the possibilities of introducing FEC intoIWSN under the requirements of the existing standard on MAC layer. Then we propose compatible and flexible FEC schemes on MAC layer for IWSNs without violating the standard format. Routing protocols based on flooding are proved to increase the Packet Delivery Ratio (PDR) by transmission diversity.We propose reliable and robust routing protocols with respect to high reliability and real time performance for IWSNs.