Worldwide Interoperability for Microwave Access (WiMAX) standard is based on the IEEE 802.16. It provides wireless broadband to fixed and mobile terminals. The demand for broadband wireless services is increasing day-by-day. WiMAX provides wireless broadband to fixed and mobile terminals. It is one of the latest developments and considered as a 4G (Fourth Generation) technology. It is based on Wireless Metropolitan Area Networking (WMAN). In this paper, Bit Error Rate (BER) of different digital modulation techniques like BPSK, QPSK, 16QAM and 64QAM are discussed.