[Objective] Quantitative analysis and understanding the role of terrace carbon sink and its characteristics are significant for further giving play to the role of terrace carbon sink, consolidating and enhancing the carbon sink capacity of the ecosystem, and aiding in the development of methods for assessing the carbon sequestration capacity of terraces. [Methods] In Wuqi County of the loess hilly and gully region, we selected terraces with operational ages between 1-7 years (T5), 8-12 years (T10), 13-17 years (T15), 18-22 years (T20) and 23-27 years (T25) for our research objects. For baseline comparison, we chose slope cropland without soil and water conservation measures, studying the capabilities of terraces in terms of carbon preservation, emission reduction and carbon sequestration across different years. [Results] ① After the transformation of slope cropland into terraces, we observed an increase in carbon preservation, emission reduction, and carbon sequestration. The annual carbon preservation, emission reduction, and carbon sequestration (0-100 cm) are 0.26, 0.05 and 1.36 t/hm2 respectively. ② Each soil layer of the terraces contributes certain benefits, the carbon sequestration benefits of the surface (0-40 cm) and deep (40-100 cm) soil layers account for 61.50% and 38.50% of the entire soil layer, respectively. ③ With the increase in the operation year of the terrace, the benefits of the terrace surface soil increased significantly, while the benefits of deep soil were slightly improved but remained stable on the whole. The rate of carbon sequestration in surface soil increased from 16.30% of T5 to 51.34% of T25, and that in deep soil increased from 14.00% in T5 to 23.66% of T25. [Conclusion] The terrace in the loess hilly and gully region exhibits significant carbon sink functions, including carbon preservation, emission reduction, and carbon sequestration. Within 27 years of the operation of the terraces, the proportion of the carbon sequestration capacity is the largest, and the increase of the surface soil is more significant. With the increase of terrace operation year, the proportion of carbon preservation in the carbon sink capacity of terrace will gradually increase.