Objective: To study the fatigue symptoms of adult patients with primary immune thrombocytopenia (ITP) and to analyze the possible factors that affect the severity of fatigue. Methods: Eligible adult patients with ITP who admitted to Institute of Hematology & Blood Diseases Hospital were enrolled in this study and the questionnaires including a Chinese version of the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) , the Pittsburgh sleep quality index (PSQI) , the Hospital Anxiety and Depression scale (HADS) and demographic information were completed. The predictors of fatigue were determined with multiple linear regression analyses. Results: A total of 207 patients with ITP were enrolled, including 70 males (33.8%) and 137 females (66.2%) , the median age was 42 (18-72) years old. The FACIT-F score in ITP patients was (37.50±9.05) . The FACIT-F severity of ITP patients was positively correlated with the platelet count (r=0.307, P<0.001) . The FACIT-F severity was negatively correlated with bleeding severity (r=-0.276, P<0.001) , sleep quality (r=-0.654, P<0.001) , depression (r=-0.598, P<0.001) and anxiety (r=-0.616, P<0.001) . A multiple linear regression analysis revealed that the severity of ITP-related fatigue was significantly correlated with platelet count (P<0.001) , bleeding severity (P=0.004) , sleep quality (P<0.001) and depression (P<0.001) . Conclusion Fatigue was determined by complicated factors in adult ITP patients. Interventions addressing depressive symptoms, sleep quality, bleeding symptoms and platelet count could be potential avenues for treatment of fatigue in patients with ITP.