In recent years, alpine meadow vegetation increasingly exhibits a phenomenon of degradation, owing to the double effects of climate change and land use change. In such situation, discussing the dynamic law of alpine meadow vegetation in climate change and human activities has great significance for the protection and effective utilization of alpine vegetation, as well as to the prevention of grassland degradation or desertification in high-altitude regions. In this research, we chose an alpine meadow of the Qinghai-Tibetan Plateau as the study area, and adopted experimental warming to simulate climate warming and clipping to mimic human grazing, and set four treatments with the random block design including control, warming alone, clipping alone, and the interaction of warming and clipping. We measured vegetation height, coverage, and aboveground biomass in the growing season (from May to September) of the alpine meadow in 2012 and 2013. The aim was to study the responses of aboveground vegetation to warming and clipping, and further explored the characteristics and trends of aboveground vegetation in climate change and human activities in the alpine meadow of the Qinghai-Tibetan Plateau. The results showed that (1) summer was the best season and July was the best month for vegetation growth in the alpine meadow. But the variations of vegetation growth properties were greater in the different months of the growing season and different years. Vegetation height was greater in the middle growing season than the early and late growing season (P<0.05), whereas vegetation coverage and aboveground biomass were greater in the middle and late growing season than the early growing season (P<0.05). Vegetation height and aboveground biomass were slightly larger in 2012 than 2013 (P>0.05), whereas vegetation coverage was slightly smaller in 2012 than 2013 (P>0.05). (2) Vegetation height, coverage, and aboveground biomass were all not significant between treatments in the second year of warming (2012, P>0.05), whereas reached significant differences in the third year of warming (2013, P<0.05). 2-year clipping significantly reduced vegetation height and aboveground biomass (P<0.05), whereas the interaction of 3-year warming and 2-year clipping significantly decreased vegetation coverage and aboveground biomass (P<0.05). The above results demonstrated that the effects of warming and clipping on aboveground vegetation of the alpine meadow had differences between short-term and long-term scales, i.e. the effects were not significant in the early stage, but enhanced with passing time. However, this conclusion needs more data to be explained deeply.