Objective: To analyze the epidemiological characteristics of HBV susceptible people in 1-29 years old people in 2006 and 2014 in China. Method: Data is from the 2006 and 2014 national sero-survey, and both of them were conducted in 160 disease surveillance points of 31 provinces (excluding Hong Kong, Macao Special Administrative Region and Taiwan province) in China. We used the centralized face-to face investigation method to collect basic information including birth date, gender, ethnicity, resident place, hepatitis B vaccination (HepB) history and so on, and 5 ml venous blood was collected for all subjects to test the sero-markers of HBsAg, anti-HBs and anti-HBc. We definite the HBV susceptible people as the HBsAg, anti-HBs and anti-HBc all negative together. And we use chi-square to analyze the epidemiological characteristics of HBV susceptibility in 1-29 years old young people in 2006 and 2014, and use multiple factors logistic regression to analyze the affect factors on HBV susceptible appearing in people with HepB vaccination. Result: In 2006 and 2014 sero-surveys, the investigated 1-29 year-old people were 49 849 and 31 713, respectively. And compared with 2006, the proportion of HBV susceptible people with HepB among 1-29 in 2014 increased from 20.87% (10 401) to 28.55% (9 055) (χ(2)=630.69, P<0.001); and the proportion of susceptible people without HepB decreasing from 15.02% (7 485) to 7.66% (2 460) (χ(2)=953.73, P<0.001). Compared with Han nationality, the high risk of susceptible appearing in minority people after HepB vaccination (OR=1.38). And compared with less than 3 doses HepB vaccination, the more than 3 doses vaccination could reduce the anti-HBs disappearing rate (OR=0.68); Compared with one year after last dose vaccination, the 2-4 years interval (OR=3.33) and more than 5 years interval (OR=6.53) would have high risk for anti-HBs disappearing. All above were P<0.001. In western area, the proportion of susceptible people without HepB (9.58%, 1 047/2 460) was higher than the proportion in eastern (6.30%, 657/2 460) and middle area (7.30%, 756/2 460) (P<0.001). Conclusion: The HepB coverage maintained in high level in 1-4 years old children. The HBV susceptible proportion mainly concentrated in 15-29 years old people, and the immunization gap was in western, rural areas and minority peoples.