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Agricultural-pastoral area of Northern China is a ecologically fragile belt. Climate change has increased the risk of ecological vulnerability in this region. Besides, it has made the ecological vulnerability more serious because of the pattern of alternant farming and animal husbandry. Therefore, the aim of this paper was to study the responses of vegetation to the change of meteorological factors in agricultural-pastoral areas of Northern China during 2001—2013, using correlation analysis method. First, temporal and spatial variation rules of vegetation growing were explored based on NDVI (Normalized differential vegetation index) and GPP (Gross primary productivity) data. Then, variation rules of temperature and precipitation were found. Finally, we analyzed the responses of vegetation to the change of meteorological factors of different vegetation types using Pearson correlation coefficient method. The results showed that in the research area, vegetation ecological situation was negatively correlated with temperature and positively correlated with precipitation in growing season, while the correlations were on the contrast in nongrowing season. The vegetation ecological situation was positively correlated with temperature and negatively correlated with precipitation. Because the higher temperature will inhibit the vegetation growth than the optimum temperature, while the precipitation in semiarid area could promote the growth of vegetation. However, temperature was very low in nongrowing season, so the increase in temperature promotes vegetation ecological situation obviously and the response of vegetation to precipitation was not obvious because precipitation was not the main factor influencing the vegetation ecological situation in this period.