Abstract: OBJECTIVE To conduct the epidemiological survey of the chronic hepatitis C virus infection patients with type 2 diabetic mellitus so as to reduce the incidence rate. METHODS A total of 444 patients with chronic hepatitis C virus infection who were treated in hospitals from Jan 2015 to Aug 2015 were enrolled in the study, then 66 chronic hepatitis C virus infection patients with type 2 diabetic mellitus were assigned as the experimental group, and 378 chronic hepatitis C virus infection patients without diabetic mellitus were set as the control group. The statistical analysis of the indicators, including the clinical data, biochemical indicators, and hepatitis C virus serum, was performed by using the self-designed questionnaire, and the epidemiological characteristics of the chronic hepatitis C virus infection patients with type 2 diabetic mellitus were observed. RESULTS Among the 66 chronic hepatitis C virus infection patients with the type 2 diabetic mellitus, the proportion of the male patients was higher than that of the female patients (P<0.05); the proportion of the patients from urban area was higher than that of the patients from the rural area (P<0.05); the proportion of the patients aged more than 60 years old was higher than that of the patients in other age groups (P<0.05). The incidence of the type 2 diabetic mellitus in the patients with chronic hepatitis C virus infection was closely associated with the age, gender, registered permanent residence, drinking history, and complication of fatty liver (P<0.05). There was no significant difference in the aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, or serum albumin between the two groups of patients. CONCLUSION Among the patients with chronic hepatitis C virus infection, the incidence rate of type 2 diabetic mellitus is relatively high in the middle-aged patients, urban residents, or patients complicated with fatty liver.