Abstract:[Objective] In order to improve the carbon sequestration capacity of terrestrial ecosystem, the impact of artificial afforestation on soil organic carbon storage in forest steppe ecotone of northern Hebei and the differences in soil carbon storage among the different plantations were studied. [Methods]Pinus Sylvestris var. mongolica and Larix gmelinii var. principis-rupprechtii plantations were selected as the research objects in the Yudaokou area located in forest steppe ecotone, with unplanted land as controls, the SOC(soil organic carbon) content and SOC storage of different terrestrial ecosystems were studied using variance analysis. [Results] (1)There was a significant positive correlation between soil organic carbon content and vegetation biomass in uncultivated forests in the Yudaokou area.(2)There were significant differences in soil organic carbon storage in different unplanted land in Yudaokou area, ranging from 31.78 t/hm2 ~ 127.56 t/hm2 (P < 0.05).(3)The larch plantation and scotch pine plantation had significantly lower soil carbon content and SOC storage than unplanted land I , but higher than that of unplanted land II and unplanted land III (P < 0.05). The larch plantation had significantly higher soil carbon content and SOC storage than scotch pine plantation (P < 0.05). The order of SOC storage from high to low in the 0-60 cm soil layer was unplanted land I (127.56 t/hm2) > larch plantation (105.26 t/hm2) > scotch pine plantation (75.52 t/hm2 )> unplanted land II (56.06 t/hm2 )> unplanted land III (31.78 t/hm2).(4) The soil organic carbon content and carbon storage of North China larch show a gradually increasing trend with age in each soil layer, from large to small, they are 26-30a, 21-25a, and 16-20a, respectively. The soil organic carbon storage of 0-60cm in each forest age is 159.73t/hm2, 112.29t/hm2, and 105.26t/hm2, respectively; The soil organic carbon content and carbon storage of scotch pine plantations show a trend of first decreasing and then increasing with age. The soil organic carbon storage of scotch pine plantations from 6-10a, 11-15a, 16-20a, and > 20a at 0-60cm depth is 79.38t/hm2, 54.24t/hm2, 75.52t/hm2, and 82.24t/hm2, respectively. [Conclusion] The impact of afforestation on soil organic carbon content and storage is related to initial conditions, and there are significant differences in soil organic carbon content and carbon storage among different types of artificial forests. In the Yudaokou area, using larch for afforestation in the place with lower soil organic carbon content and storage can obtain higher soil carbon storage.