As global warming intensifies, regional thermal environment problems are becoming increasingly prominent. Therefore, the cooling effect of vegetation has gradually gained widely attention. Existing studies mostly analyzed the cooling effect of different types of vegetation from plot-scale. However, studies on region scale mostly focused on the qualitative analysis of relationship between vegetation parameters and surface temperature. Due to lack of comparative analysis between test plot and control plot, there have certain limitations for evaluate actual cooling effect and calculate corresponding cooling value. Using the nearest neighbor analysis in this article, the MODIS surface temperature of forest, shrub and grassland were compared with the surface temperature of low coverage to analyze the cooling effect of vegetation. The range of the control area was selected as 5km because adequate control plots were found within this distance. The regression fitting was used to analyze the influence of vegetation coverage on cooling effect. According to the results, cooling effect in Eastern Inner Mongolia, Central Inner Mongolia, and Inner Mongolia-Gansu subregions all showed forest > shrub > grassland. The range of temperature reduction in forest was 0.67-1.03℃, that in shrub was 0.60-0.95℃, and that in grassland was 0.47-0.86℃. The regression fitting of vegetation cooling degree and vegetation coverage was logarithmic distribution, and which showed significantly positive correlation (P < 0.01). When the vegetation coverage level is lower (< 40%), the increase of vegetation coverage can significantly reduce the surface temperature. For example, every 10% increase in low coverage forests (< 40%), the range of temperature reduction was 0.20-0.27℃, that in medium coverage forests (40%-60%) was 0.12-0.16℃, and that in high coverage forests (>60%) was 0.07-0.10℃. Differences in the cooling effect of different vegetation coverage may be affected by multiple factors such as vegetation transpiration, surface reflection, shading, roughness, and so on. The results showed that trees can effectively block direct sunlight, and the cooling effect is significantly higher than that of shrubs and herbs. For instance, every 10% increase in vegetation coverage would result in forest cooling of 0.12-0.39℃, shrub cooling of 0.1-0.2℃ and grassland cooling of 0.049-0.075℃. In conclusion, Inner Mongolia is one of the most sensitive regions to global climate change. To study the cooling effect of vegetation can provide importantly theoretical support and case reference for the assessment of climate regulation services in the Inner Mongolia.