Climate warming and humidification has important practical significance for vegetation growth and coverage, as well as rational land development and utilization and ecological environment protection. Taking Mu Us sandy land as the study area, based on the meteorological data (temperature, precipitation and evaporation) from 1959 to 2019, this paper analyzed the characteristic changes of climate warming and humidification by using climate trend change, M-K mutation and wavelet cycle, and explored the response relationship between it and meteorological factors in the study area based on normalized difference vegetation index (NDVI) value in the growing season. The results showed that: (1) During the study period, the annual average temperature, annual average precipitation and annual average evaporation in Mu Us sandy land increased by 1.7 ℃, 11.19 and 33.82 mm, respectively, and showed a significant upward trend. (2) The 1970s was the starting time of the sudden change of meteorological factors, and the sudden change of temperature from cold to warm, precipitation from less to more, and climate from dry to wet occurred from 1970s to 1990s. (3) The annual average temperature, precipitation and evaporation in the sandy land oscillated most obviously in the period of 20~30 years, and reached the peak at 28 years, which was the first main period of the change of meteorological factors in Mu Us sandy land. (4) From 1998 to 2019, NDVI generally showed a fluctuating and increasing trend, which was positively correlated with evaporation and precipitation. The significance of evaporation was greater than that of precipitation. The research results could provide a scientific basis for the effective protection and management of these valuable ecosystems under the current climate change.