Coarse wavelength division multiplexing (CWDM) is a low cost and high reliability communication technology, which is widely used in broadband metropolitan area network. Based on CWDM technology, an optical transceiver module with the speed of 100 Gbps and according with the industry standards is developed. QSFP28 packaging is adopted, and the transmitting and receiving performances of the module are tested and optimized. After testing, the transmitting eye map meets the needs of 30% margin, the receiving sensitivity is less than -10 dBm, which can meet the requirements of high rate data communication system.