OBJECTIVE To evaluate the econo mical efficiency of Recombinant human thrombopoietin injection （called “rhTPO”for short ）versus Etrapopa ethanolamine tablets （called“Etrapopa”for short ）in the second-line treatment of primary immune thrombocytopenia （ITP）in the Chinese adult patients. METHODS Based on the decision tree-embedded Markov model with a 4-week cycle ，the cost and utility related to bleeding events and adverse events after the use of the two drugs were measured and compared from the perspective of Chinese health system. The horizon was 12 weeks，and the cost and health outcome were not discounted. RESULTS Compared with Etrapopa ，rhTPO improved the quality adjusted life year by 0.002 5 and reduced the cost by 1 824.36 yuan，which was the absolute advantage scheme. Univariate sensitivity analysis showed that the base results were greatly affected by the dosage of rhTPO and Etrapopa during maintainance period. In most cases ，rhTPO was economical. Probability sensitivity analysis showed that when willingness-to-pay threshold varied between 0 yuan and 250 000 yuan，the probability about that rhTPO was economical ranges from 99.90％ to 100％. CONCLUSIONS Based on the available evidence ，rhTPO is more economical in the short term than Etrapopa in the second-line treatment of ITP.