Abstract: Based on a set of gridded chinese regional daily observations（CN05.1）and the normalized differential vegetation index（NDVI）spatial distributions,the 50-year spatial and temporal variability of temperature and precipitation in the sandy area of western Inner Mongolia and its 21-year vegetation response were analyzed.The results showed that the temperature increased with a rate of0.447 ℃·（10 a）-1with one significant abrupt change in the sandy region of western Inner Mongolia from 1969 to 2018.The precipitation increased with a rate of 4.533 mm·（10 a）-1,with three abrupt changes.Prominent variation in temperature and precipitation in Bayannur and southeastern Ordos appeared,with significant spatial heterogeneity.The NDVI in the sandy region of western Inner Mongolia increased significantly at a rate of 0.01·（10 a）-1from 1998 to 2018,with the most significant increase in southern Bayannur,Erdos and southeastern Alashan.The NDVI had positive correlations with precipitation and temperature during the growing season from 1998 to 2018,with precipitation having a greater impact than temperature.The sandy region of western Inner Mongolia showed a warm and humid trend and the vegetation was improving.