Abstract: Based on the estimation of carbon sink of farmland soil ecosystem in Shaanxi Province from 2005 to 2020,used the methods of standard deviation ellipse, spatial autocorrelation, cold and hot spot analysis to study the spatial-temporal evolution characteristics of its carbon sink, in order to reveal the spatiotemporal heterogeneity of soil carbon sink and reasonably formulate regional appropriate farmland management policies.The results showed that, 1) From 2005 to 2020,the total amount of soil carbon sink in Shaanxi farmland showed a fluctuating upward trend, from 58.83×10~4 t per one year to 76.51×10~4 t per one year.The type of carbon sink was mainly fertilizer carbon sink.2) The spatial distribution pattern was ‘high in the middle and low in the north and south’.High-value areas were mainly distributed in Xianyang, Weinan, Xi′an and Baoji, while low-value areas were distributed in Yulin, Ankang and Shangluo.3) The center of gravity of the spatial distribution had the trend of moving to the north and slightly to the east, and the distribution scope had the trend of contracting first and then expanding.The influence of the northwest region on the overall spatial pattern of carbon sinks had been strengthened.The intensity of soil carbon sink had a positive spatial correlation, and the spatial distribution and concentration of cold and hot spots showed a fluctuating and stable feature.