Based on NOAA data, this paper analyzed the process of land cover change and climate change trend in the source region of Yellow River from 1990 to 2000 by BP neural network. Moreover, the relationship between land cover change and climate change was analyzed by partial correlation model. The results showed that the desertified land area was dramatically increased with a continuous downward trend of average vegetation coverage. Whereas the average annual average temperature and average annual maximum temperatures were obviously increased, and average annual minimum temperature was also on the rise, but the average annual precipitation was presented fluctuant decrease. Correlation analysis showed that the areas of different land covers had different relationships with various meteorological factors. Climate change was an important driven factor for the land cover change in the study area.