OBJECTIVE：To pr ovide reference for the future pharmacoeconomic evaluation. METHODS ：Four typical cases of pharmacoeconomic evaluation showed the special situation that “not cost-effective at a zero price ”，defined the concept of “net value”to assist in theoretical analysis ，and summarized the possible causes of this situation . RESULTS & CONCLUSIONS ：The system（ATPS）：an overview and advances in its applica background treatment cost other than the target drug was too high ，the patient ’s quality of life during survival was too low ，the threshold of willingness to pay of incremental cost-effectiveness ratio was too low ，the cost of risk events during extended survival was too high or the health loss was too high ，and the price of the control scheme was too low ，which might affect the results of economic evaluation ，and even le d to the dilemma of pharmacoeconomic evaluation of “not cost-effective at a zero price ”. Pharmacoeconomic evaluation discusses the economy of intervention programs rather than the economy of drugs. The uneconomic results caused by various reasons need to be treated objectively ；theoretically，all“relevant”and“irrelevant”costs should be included in the calculation category in pharmacoeconomic evaluation ；pharmacoeconomics mainly solves the problem of “cost performance”comparison among several treatment schemes ，and the medical and health field often needs to face problems such as ethics and fairness. Therefore ，researchers may need to jump out of the framework of pharmacoeconomics analysis and conduct in-depth discussion from a higher and broader perspective.