Medicine is a very important health resource in China. Although numerous efforts are paid to pre-marketed medicines, little is done to address practical problems in marketed medicines. The rational use and allocation of marketed medicines remain a major concern for decision-makers in China. It has been recognized that economic evaluation is an efficient tool for prioritizing the choice, and optimizing the use of medicines. This paper has explored the methods and principles for conducting economic evaluation of marketed medicines. Different strategies will be adopted for economic evidence for marketed medicines in terms of adequacy and sufficiency.However, a standard study pathway should be applied in economic evaluation of marketed medicines. Besides, the aspects for developing economic framework and the methods for reviewing existing economic evidence are also introduced in this paper, particularly, for marketed medicines within the same therapeutic group.