The temperature of sand dunes with eco-mat and without eco-mat in Hexi Corridor of Gansu Province was measured continuously in August，2004. The results showed that，eco-matting can effectively reduced the mean diurnal soil temperature and mean temperature of each layer (0，5，10，15，20 cm )，the mean daily soil temperature decreased about 5. 5℃，4. 0℃，2. 4℃，2. 1℃and 1. 6℃respectively if coveyed by eco-mat. The eco-matting also reduced the temperature difference of each layers, compared with the contrast of mobile dunes, the temperature difference after eco-matting were 8. 8℃，5. 0℃，4. 5℃，2. 8℃ and 2. 8℃from 0 cm to 20 cm respectively. Additionally, variance of soil temperature of each layers also tend to decreased as the soil depth going down. We can roughly concluded that eco-mat can effectively reduced soil temperature of the soil layer from 0 cm to 15 cm, and effectively slowed down the variance of soil temperature, both of which may benefit to reduce soil evaporation under high temperature.