Soil organic matter (SOM), soil total nitrogen (STN) and soil available phosphorus (SAP) are key indices of evaluating soil fertility and quality, and also play an essential role on the crop growth. The spatial and temporal variability of SOM, STN and SAP in the arable lands in Wugong County in Loess Plateau in China base on the second national soil survey with 335 soil samples data in 1981, evaluation of potential productivity of arable lands with 187 soil samples in 2006 and soil carbon survey of arable lands with 70 samples in 2011 were studied using the geo-statistics and GIS method in this contribution. The objective of this study is to know about the variability of the soil nutrients and provide right fertilizing guide for the regional sustainable development and agricultural environmental protection and agricultural production. Descriptive statistics of the results showed that mean of SOM, STN and SAP were 10.31 g kg^-1, 0.077g kg^-1 and 8.59 mg kg^-1 in 1980 respectively; that of SOM, STN, and SAP were 14.89 g kg^-1, 0.12g kg^-1 and 23. 9 mg kg^-1 in 2006 respectively; whereas the average contents of SOM, STN and SAP in the county arable lands in 2011 were 17.37 g kg^-1, 0.11 g kg^-1 and 22. 18 mg kg^-1 respectively. The content of SOM, STN and SAP increased significantly by 43.31%, 55.84% and 57.44% respectively from 1980 to 2006. The content of SOM, STN and SAP did not change obviously from 2006 to 2011. Geo-statistical analysis indicates that there have a strong spatial autocorrelation and structural factors played a dominating role in spatial variability of SOM, STN and SAP in this area which were significant in anisotropy at 45° of direction in 1981 and in isotropy in 2006 and 2011; The relationship between the contents of SOM, STN and SAP and topography were analyzed in 1981, 2006 and 2011. The results suggested that the content of SOM, STN and SAP are higher in lowland than upland and increasing from north to south in 1981. The spatial patterns of SOM, STN and SAP were analyzed with Kriging interpolation and calculating in 1981, 2006 and 2011. The main reason for increasing of the content of SOM, STN and SAP from 1981 to 2006 is that the mount of nitrogen and phosphorus fertilizer and organic manure were applied excessively as well as straw returning for a long time.