Artificial forest plays an important role in the buildup of forest carbon sink. However, successive rotations of fast-growing species cause soil degradation, which lead to the apparent decline of the tree growing rate. This paper aims to investigate the effects of sawdust biochar and chicken manure biochar on biomass, carbon concentration and carbon storage in different organs of Pinus Elliottii. The results showed that feedstock decided the biochar properties. After pyrolysis, the pH of sawdust biochar (7.46) was lower than the sawdust pH of 8.25, while the pH of chicken manure biochar (10.48) was higher than the pH of chicken manure (9.35). The elements of C, N, P and K were enriched during sawdust and chicken manure biochar pyrolysis. And contents of N, P and K in chicken manure biochar were significantly higher than those in sawdust bicochar. The percentages of available P and K in total P and K were reduced after feedstocks were converted to biochars. After one year experiment, chicken manure biochar significantly increased biomass in different organs of Pinus elliottii. The increment of tree aboveground biomass in the chicken manure biochar treatment was 4.92 times of that in the control, while sawdust biochar had no significant effect on tree growth. And chicken manure biochar and sawdust biochar had significant effects on the distribution of increased biomass in leaf and bark of Pinus Elliottii. No significant differences on carbon concentration in different organs of Pinus Elliottii were found in both biochars treatments. Annual net carbon fixations (ANCF) in different organs were significantly increased in the treatment of chicken manure biochar. And ANCF of tree aboveground in the treatment was 5.02 times of that in sawdust biochar treatment and 3.87 times of that in the control, respectively. Thus, chicken manure biochar could be used as an amendment to increase productivity of artificial forest. However, the effects of different biochars on the properties of soils need further research.