Objective: The paper analyzes the reason of lack of pricing space in economic evaluation of new antitumor drugs and explores the solutions. Methods: Based on theoretical analysis and case study, the paper analyzes the contents of cost and health outcome for the study group and control group, the sources of difference between groups and the criteria for economic evaluation in economic evaluation of new antitumor drugs, to explore the reason of lack of pricing space for new drugs. Results: Health outcome (QALYs), expenditure of drugs, and medical expense for prolonging patients’ life are keys for economic evaluation. If incremental medical expense for prolonging patients’ life was too high, and the increment of the study group approaches or exceeds the monetary value increment of QALYs, the space for new drug costs is limited, resulting in a lack of pricing space for new drugs. Conclusion: The cost of prolonging the survival time of patients with tumor is the huge resource consumption. In order to give new drugs pricing space, it is necessary to increase the willingness to pay for health or reduce the resource consumption of tumor treatment.