Abstract: By using the NCEP reanalysis water vapor transport flux data, the Doppler radar echoes in middle plateau of TIPEX, the satellite water vapor imagery, the time cross-section of satellite remotely sensed TBB and the dynamic variation of satellite images, the relationship between water vapor transport features of Tibetan Plateau-Monsoon "Large Triangle affecting region" and drought-flood abnormal of China has discussed in this study. It is shown that the water vapor channel is related to the outbreak of Asia monsoon, air-land process on the Plateau and the special abnormal structure of water vapor over the Plateau. The functions of heat sources in low and middle latitude oceans all appear in this area, namely the area where exists the interaction between Plateau and monsoon as well as activit ies for its members. This "large triangle" affecting of the Plateau and monsoon has been described. Thus, the southerly water vapor transport feature in the "large triangle" affecting region shows that there exists teleconnection between the Plateau and low latitude ocean heat sources and water vapor sources.