Objective To study the correlation between traditional Chinese medicinal（ TCM） constitutions type and chemotherapy-induced thrombocytopenia（ CIT） of patients with primary non-small cell lung cancer（ NSCLC） undergoing chemotherapy of gemcitabine plus cisplatin（ GP）. Methods A total of 165 patients were investigated and assessed by general condition questionnaire and classification and definition type of Chinese Medicinal Constitution Questionnaire before the first chemotherapy. During the chemotherapy time

the conditions of patients’ blood platelet was followed up and recorded by CIT of genetic terminology for adverse events 4. 03 by The National Cancer Institute.Spearman rank correlation analysis was used to analyze the correlation between Chinese medical constitution and CIT

and the difference of CIT in various constitutions. Chi-square test and Binary Logistic regression was used to analyze the risk factor of CIT. Results The constitution type of patients initially confirmed as NSCLC were chiefly mild constitution

accounting for 41. 8%. Biased constitutions were mainly yang-deficiency constitution

qi-deficiency constitution and yin-deficiency constitution. Blood-stasis constitution and heat-dampness constitution were not found in this study. There was positive correlation between TCM constitutions and CIT in NSCLC patients（ r = 0. 421

P <0. 01）. Comparisons between CIT in mild constitution and yang-deficiency constitution

qi-deficiency constitution and yin-deficiency constitution had statistical significance（ P < 0. 01）. Binary logistic regression indicated that TCM constitutions type and age were risk factors of CIT（ P < 0. 01）. Conclusion TCM constitution type was related to CIT. Patients belong to yang-deficiency

qi-deficiency and yin-deficiency are prone to have CIT

and patients aged older than 60 were more likely to have CIT.