Due to climate change, the regional agro-climatic conditions in Southwest China have undergone changes. The heat sources for the growth of crops have been improved. The number of days with temperatures steadily above 0?C and 10?C (two criteria) have increased during 1960-2010. The area suitable for multiple cropping has increased;the growth period has shortened; the climatic potential productivity has declined; the pest damage has worsened. During 1961-2010, the desired cooling degree days in Southwest China has increased 38.9?C d per decade. Forest fires and pests have increased. The area of meadow and wetlands has decreased. Heterogeneous invasion has intensified; endangered animal and plant species have increased. The tourism landscape has been damaged. The risk of human health has increased. In the 21st century, with the increase of temperature and precipitation, the number of days with temperature steadily above 10?C and the accumulated temperature will continue to increase, most notably in the Qinghai-Tibetan Plateau. The area of intercropping will expand; multiple cropping will move to higher altitudes. The impacts of agro-meteorological disasters, pests and diseases will intensify. The summer cooling energy consumption continues to increase;energy supply will show larger variability;the gap between energy supply and demand will be widened. The phenology will keep on changing, and the habitat will be worsening. Biological population will move northward and to higher altitudes. Some species are at risk of extinction. Negative effects on health will increase.