Objective To quantify the medical expenditure per case of patients with hepatitis B virus- related diseases in Qidong,Jiangsu,China,and analyze its composition and related influencing factors. Methods Cluster sampling was used to select consecutive cases in The People's Hospital of Qidong and Qidong Infectious Diseases Hospital. A total of 217 hospitalized patients of HBV related primary liver cancer,234 hospitalized patients with HBV related B cirrhosis,and 136 hospitalized patients with chronic hepatitis B( CHB) were enrolled,and the total inpatient and outpatient costs( medical costs per case) from January 2010 to December 2012 and related clinical data were collected from the hospital records. Expert consultation was performed to investigate the costs per case of patients with acute hepatitis B,HBs Ag asymptomatic carriers,and occult HBV infection. Costs in different years were converted based on the consumer price index for medical and health consumption in 2014. The independent samples t- test was used for comparison of continuous data between groups,an analysis of variance was used for comparison between multiple groups,and the SNK- q test was used for comparison within each group. Multiple linear regression analysis( stepwise regression) was used to investigate the influencing factors for medical costs per case. Results The medical costs per case of patients with HBV related primary liver cancer,patients with HBV related cirrhosis,and CHB patients from 2010 to 2012 were30183 RMB,22066 RMB,and 15703 RMB,respectively,and the inpatient costs were 29058 RMB,21383 RMB,and 15394 RMB,respectively,which accounted for 96. 3%,96. 9%,and 98. 0% of the medical costs per case. Drug costs of these three groups accounted for55. 0%,73. 4%,and 78. 2% of the medical costs per case,respectively. The number of times of hospitalization( F = 89. 1,67. 7,and11. 5,all P < 0. 001),treatment regimen( F = 21. 8,t =- 2. 1,and t =- 3. 7,P < 0. 001,P = 0. 039,and P < 0. 001),and type of medical insurance( t = 3. 1,2. 6,and 2. 7,P = 0. 002,0. 011,and 0. 012) were influencing factors for medical costs per case,while clinical stage was an influencing factor for medical costs per case only in CHB patients( a multivariate analysis for patients mild,moderate,and severe CHB: β = 1. 238,F = 5. 9,P = 0. 021). The medical costs per case for patients with acute hepatitis B were 5950 RMB,and the annual medical costs for HBs Ag asymptomatic carriers and patients with occult HBV infection ranged from 770 RMB to 1540 RMB. Conclusion The medical costs of HBV related is increasing as the illness progresses. Our results will provide baseline information for the following economic evaluation of vaccination or screening interrention.