Flood and drought disasters occur frequently in Mekong River basin owing to ocean climate and climate change. The Lancang-Mekong Cooperation and China-Asean Cooperation Mechanisms are the important content of the development of China's peripheral diplomacy. Based on the collected floods and droughts in Mekong River basin in recent years, the losses, causes and effects of flood and drought disasters are analyzed. The main conclusions are drawn as follows: The floods and droughts are the main disaster form in Mekong River basin, and the number of floods in 4 countries accounts for about 50% of the total natural disasters. The effects of floods and droughts on the population, transportation, agriculture and economy of various countries in the basin are all significant. The climate change is the main cause of the flood and drought disasters in Mekong River basin.