Based on TBB data in summer from 2007 to 2011,Banded MCSs(BM) over the Tibet Plateau with stable characteristics are screened out and classified.Causes for BM are discussed in different types by combining with NCEP data and HYSPLIT model.Results show that 37 cases of BM with stable characteristics fall into three types according to their shapes:North convex type(NCT),south boundary type(SBT) and zonal type(ZT).NCT BM are the most while ZT BM are the fewest.These BM occur in 30% time of the whole summer,especially in nearly 50% time of July.The main causes for BM include South Asia high and jet stream on upper level,shear line with convergence at 500 hPa and the air of high temperature and humidity in the south of shear line.At 500 hPa,ZT BM commonly occur between westerly airflow in north side of plateau and eastern airflow in south side of plateau.NCT BM occur under the synoptic situation that there is lank westerly airflow in northern plateau,strong trough in Bay of Bengal and influence of flow from southwest by south on eastern and southern plateau.In the process of SBT BM,there is usually northwest airflow over the plateau and strong cyclone in the south in Bay of Bengal.There are four vapor divergence regions around the plateau and vapor in convective zone mainly derives from south side of southwest edge and southeastern plateau.