Snow cover, as an important part of land cover, is one of the most active natural elements on the earth surface. This program used the MODIS/Terra-Aqua daily snow products (MOD10A1 and MYD10A1) and AMSR-E/Aqua daily snow water equivalent product (AE_DySno) from 2003 to 2010 of Tibetan Plateau (TP), together with systematic study on MODIS daily snow cover product composite and a merging of multi-sensor and snow line approaches (Liang et al. 2008) to put forward a new snow cover mapping algorithm. Daily cloud-free snow cover images were calculated based on the new algorithm and the response of climate change on snow cover dynamics was analysed