Based on the Normalized Differential Vegetation Index (NDVI) dataset obtained from the Advanced Very High Resolution Radiometer (AVHRR) of the National Oceanic and Atmospheric Administration (NOAA), as well as the high-resolution near-surface air temperature and surface precipitation rate of China meteorological forcing dataset (CMFD) from 1982 to 2018, the variation characteristics of vegetation and their response to climate warming and humidification in Qinghai Plateau during the growing season (May-September) were studied. The methods used in this study include linear tendency estimation, M-K test, partial correlation and analysis of variance, etc. The results show that: (1) During the growing season of Qinghai Plateau from 1982 to 2018, the vegetation exhibits a spatial distribution feature that decreases gradually from southeast to northwest, and there is a significant increasing trend overall with a climate tendency rate of 0.01/10a. However, the trend of vegetation has a bi-polar development feature in space, that is to say, while the vegetation in the eastern and southwestern parts of the Qinghai Plateau improves significantly (57.3% of the total area), the vegetation of the Qaidam Basin in the northwestern part of the Qinghai Plateau shows a deterioration trend (14.8% of the total area). (2) During 1982-2018, the climate of the Qinghai Plateau is characterized by warming and humidification as a whole, but there are differences in the regions and intensities of climate warming and humidification in different periods. The warming in P1 period (1982-1998) was stronger than that in P2 period (1998-2018), and the humidification in P2 period was stronger than that in P1 period. The trend of NDVI in the growing season of Qinghai Plateau shows a significant mutation around 1998. Before 1998, it fluctuates with no obvious trend, but after 1998, it shows a significant increasing trend, which is consistent with the warming and wetting trend of the Qinghai Plateau vegetation. (3) There is an interdecadal variation in the response of surface vegetation on the Qinghai Plateau to climate warming and humidification. In P1 period, the heat factor (air temperature) inhibits the growth of surface vegetation under insufficient water conditions, while in P2 period, under relatively sufficient water conditions, both water and heat factor promote the growth of surface vegetation. Therefore, the surface vegetation of Qinghai Plateau vastly improves in the growing season.