Telecommunication industries are highly concerned with the wireless transmission of data which can use various transmission modes, from point- to-multipoint links. It contains full mobile internet access. Various applications have already been applied so far using WiMAX, as alternative to 3G mobile systems in developing countries, Wireless Digital Subscriber Line, Wireless Local Loop . IEEE 802.16e-2005 has been developed for mobile wireless communication which is based on OFDM technology and this enables going towards the 4G mobile in the future. In this thesis work, we built a simulation model based on 802.16e OFDM-PHY baseband and demonstrated in different simulation scenarios with different modulation techniques such as BPSK, QPSK and QAM (Both 16 and 64) to find out the best performance of physical layer for WiMAX Mobile. All the necessary conditions were implemented in the simulation according to 802.16e OFDMA-PHY specification. The noise channel AWGN, Rayleigh fading, SUI, data randomization techniques, FFT and IFFT, and Adaptive modulation is used for the whole simulation procedure. Performance has been concluded based on BER, SNR and Pe output through MATLAB Simulation.