Broadband wireless communication in Metropolitan Area Networks (MANs) is done through the IEEE 802.16 standard, also known as Wi-MAX. To achieve a good and efficient Quality of Service (QoS) in a Wi-MAX network, rate allocation is necessary. Rate allocation also provides fairness among the users. In this paper, the authors propose performance evaluation of Wi-MAX network based on transmission rate. By the simulation results, they deduce that the proposed scheme reduces the average delay and improves the average throughput. The Qualnet 6.1 simulator was used to carry out the simulation.