Abstract: In this paper, the years of st rong and weak South Asian summer monsoon are chosen by the EOF analysis of the NCEP/NCAR wind data. And then the cloud-radiation-heating state over the Tibet an Plateau in the early days (April-May) of the strong and the weak South Asian summer monsoon is analyzed and its effect on sea-land thermal contrast is discussed by using the ISCCP-C2, ERBE-S4 satellite observation data and t he NCEP/NCAR data. Results show t hat differences bet ween the early days of the strong and the weak South Asian summer monsoon in cloud-radiation-heating state and effect are obvious. In the early days of the strong South Asian summer monsoon, there is relatively less cloud cover over most areas of the Tibet an Plateau, the short wave radiat ion cloud-forcing is little. According ly, the netradiation flux of the earth-atmosphere system is increased and the earth-atmosphere system is heated. During the same time, the difference between temperate latitude and tropical zone is negative for the cloud cover anomalies and that is positive for the net radiation anomalies, the sea-land thermal contrast is intensified. But in the early days of the weak South Asian summer monsoon, the cloud-radiation-heating state and effect are contrary to the strong case. It is evident that the cloudradiation-heating state over the Tibet an Plateau in the early days of the South Asian summer monsoon playsavery important role in activities of the South Asian summer monsoon.