Objective: To understand epidemiological characteristics and influencing factors of hepatitis B virus (HBV) carriers progressing to chronic hepatitis B in Jiangsu, and provide evidence for regular management of HBV carriers. Methods: From 2012 to 2014, a cohort study was conducted among the HBV carriers in an area in Jiangsu province. Association between HBV carriers' demographics, HBeAg level and HBV DNA detection result and incidence of chronic hepatitis B was analyzed by Cox regression analyses. Results: In 2012, a total of 4 069 HBV carriers aged (52.0±12.8) years were surveyed. By 2014, chronic hepatitis B had developed in 1 444 cases, with the rate of 21.0/100 person-years. Cox regression analysis indicted that, in addition to gender, HBV DNA level was an important influencing factor for the incidence of chronic hepatitis B (P<0.05). In HBeAg positive carriers progressing to chronic hepatitis, 40.7% had HBeAg seroconversion, and reversion of HBeAg occurred in 1.7% of HBeAg negative carriers. Conclusion: Chronic hepatitis B developed in more than 1/5 (21.0/100 person-years) of HBV carriers in the surveyed area in Jiangsu. It is suggested to conduct regular ALT, HBV DNA detection and B ultrasonic examination in HBV carriers for the early detection of chronic hepatitis B.