Objective To Study the design and material selection of envelope packaging composite materials. Methods The function mechanism of envelope packaging was briefly introduced , the moisture barrier property, usability, environmental suitability and manufacturability were analyzed, the influencing factors on moisture barrier performance were analyzed based on the environment and material characteristics, and the structure design as well as functional material selection were studied. Results The multilayer structure design, functional materials selection and key attention points were summarized and analyzed. Conclusion The performance design, structure design, and functional material selection must first of all meet the packaging protection requirements of the equipments, and meanwhile take account of the usability and economical efficiency.