The aim of this work was to propose the theory and method for selection of green materials in package design. Based on the life cycle design， the functionality, economy and environmental benefits of materials were analyzed, the recycle patterns of package materials was discussed, and the economy evaluation model for selecting green packaging materials was constructed. Material selection of a disposable beverage cup was illustrated as an example using the proposed method. The priority levels of material characteristics selection under different modes were listed in the aspect of functionality. The impact factors on material selection according to environmental benefits were put forward. A TOPSIS algorithm was proposed to obtain optimal solution and comprehensive assessment of green packaging’ s material selection. In conclusion, getting the comprehensive solution of economic cost model and environmental benefits using the TOPSIS algorithm was beneficial for the selection of the best one from many materials which tally with life-cycle of material circulation model and priority level of material characteristics selection.