Artemisia ordosica biochars were prepared under anaerobic carbonization condition at different temperatures and added into the sand in order to identify their organic components, carbonization process and degradation characteristics under different carbonization conditions. The results showed that the mass fraction of H, O and N elements, H/C, O/C and ( N + O)/Cdecreased first and then tended to stable with the increase of temperature and carbonization time, but they were not affected obviously by the heating rate, while C showed the opposite trend and it was near stabilized after carbonization temperature > 600 ℃, the carbonized time > 60 min. The stable values of the above indexes were about 29.3 g/kg, 79.8 g/kg, 11.2 g/kg, 0.40, 0.07, 0.08 and 879.7 g/kg, respectively. Degradation rate of biochar was reduced with the increased carbonization temperature, extended carbonization time and increased amount of biochar, its half-life was about 2-12 years. In conclusion, the biomass heating pyrolysis is a process in which carbon enriched and polar functional groups cut, meanwhile aromaticity increased but hydrophilic and polarity weakened, and application amount and carbonization temperature are the decisive factors in influencing degradation of biochar.