Abstract: Objective To investigate the epidemic status of Eperythrozoon infection and related infection factors in patients with tumors. Methods A total of 106 patients with cancer and 114 patients of healthy physical examination were recruited by random sampling method from August 2016 to July 2018. The EDTA-K₂ anticoagulant whole blood were collected and stained by Wright staining and acridine orange fluorescence staining to determine the infection of Eperythrozoon. Both of them were positive for Eperythrozoon infection and all the relevant information (age, gender, whole blood count, treatment etc) was collected. Chi-square test were applied to analyze the difference of positive rates. Results The corresponding infection rates in the patients group and health control group were 33.02% and 11.40%, and there were significant statistical difference among them (χ²=15.045, P<0.001). There was no significant difference in the infection rate of Eperythrozoon in tumor patients in different systemic tumors, intervention treatment, erythrocyte blood count, platelet count, age distribution and gender distribution (all P>0.05). The trend of increased rates of infection in increased white blood cell count group was reflected (χ²=2.885, P=0.089). The infection rate of Eperythrozoon in healthy persons has no statistical significant difference between children and adults (χ²=0.492, P>0.05). Conclusion There was mild infection of Eperythrozoon in patients with tumor and healthy people, but the infection rate of patients with tumor was significantly higher than that of healthy people; The tumor patients with the increased WBC count maybe infected with human eperythrozoon; The infection rate of human erythrocyte in patients with tumors is not related to the factors of intervention treatment, tumor system, red blood count, platelet count, age, gender etc. The infection rate of human erythrocytes in healthy subjects was not related to age.