GIMMS NDVI data from 1982 to 2006 were adopted to reflect the time series characteristics of vegetation change in North China. The relationship between vegetation coverage changes and climatic variations from the yearly, seasonal and monthly time scales were analyzed combined with temperature and precipitation data of 85 meteorological sites. The results showed that vegetation coverage change was closely correlated with climatic factors, and the correlations were different on different time scales. Annual average of vegetation change was better correlated with temperature than precipitation. Correlations between seasonal average of vegetation coverage and climatic factors showed that the sensitivity of vegetation growth to hydrothermal condition change was different in different seasons. The sensitivity of vegetation growth to temperature in both spring and autumn was higher than in summer, especially in spring, while that of vegetation growth to rainfall in summer was higher. Correlations between monthly average of vegetation coverage and climatic factors showed that the response of vegetation changes to temperature in April and May was stronger, indicating that the temperature effect occurred in the early stage of vegetation growth. Correlations between NDVI of the current month and precipitation of the month before last were better from June to September, showing a hysteresis response of vegetation growth to rainfall.%利用1982-2006年GIMMS NDVI数据反映华北地区植被覆盖变化状况,结合1982-2006年该地区85个气象站点的气温和降水数据,分别从年际变化、季节变化和月变化三个时间尺度分析华北地区植被覆盖变化及其与气候变化的关系.结果表明,从年际变化来看,华北植被变化与气温变化关系较与降水关系密切；从季节变化来看,华北地区植被生长在不同季节对水热条件变化的响应不同,春季和秋季植被生长与气温的关系较与降水的关系密切,而夏季植被生长主要受降水的影响；从月变化来看,4月和5月植被变化受气温变化影响较明显,一定程度上说明4月和5月植被生长的NDVI值增加可能是由于气候变暖引起的植被生长季提前产生的；6-9月植被生长与前2个月降水变化关系密切,说明植被生长对降水变化具有一定的滞后性.
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