This study aimed to investigate the dynamic changes of serum HBV DNA and hepatitis B surface antigen (HBsAg) titers apportioned by the same hepatic parenchyma cell volume (HPCV) at different liver histological inflammation grades in the natural history of chronic hepatitis B (CHB). The serum HBV DNA and HBsAg titers were detected by real-time polymerase chain reaction and electrochemiluminescence, separately, in CHB patients without any treatment. The serum HBV DNA levels and HBsAg titers apportioned by the same HPCV were figured out based on sphere geometry theory. In addition, the differences of HBV DNA levels and HBsAg titers apportioned by the same HPCV in different liver inflammation grades were further assessed based on statistical analysis. There was no difference of serum HBV DNA levels or HBsAg titers before apportioned by the same HPCV in liver inflammation grades 1-4, but significant differences were observed after apportion in CHB patients (HBV DNA: P=0.101; HBsAg: P=0.211 & HBV DNA apportioned by HPCV: P<0.001; HBsAg apportioned by HPCV: P<0.001). No correlation was observed between HBV DNA levels and liver inflammation grades (r=0.083, P=0.186), or between HBsAg titers and liver inflammation grades (r=0.083, P=0.078). A significant correlation was observed between HBV DNA levels apportioned by HPCV and liver inflammation grades (r=0.249, P<0.001), and obvious correlation of HBsAg titers apportioned by HPCV and liver inflammation grades was also found in CHB patients (r=0.554, P<0.001). These results suggest that the levels of serum HBV DNA and HBsAg apportioned by the same HPCV are correlated with the severity of liver histological inflammation grade in the natural history of CHB.