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The dynamics of vegetation cover changes may provide vital information for ecological environmental protection and early warning of ecosystem degradation in arid and semiarid regions. The West Liaohe River Basin is the east fringe of agro-pasture transitional zone in northern China and highly sensitive to global change. With the SPOT VEGETATION (SPOT-VGT) NDVI dataset during 1999-2010, temporal and spatial change trends of vegetation cover was investigated using yearly and seasonal average NDVI, Vegetation Anomaly Index (VAI) and correlation analysis. The relationship between vegetation change, climatic and anthropogenic factors were explored. The results indicated that yearly NDVI slightly increased with an undulating trend. 30.24% of the study area had experienced a significant vegetation increase at the 0.05 level from 1999 to 2010. The VAI negative values exhibited vegetation cover degradation impacted by the drought in 2000-2002 and 2009. The average NDVI values in autumn increased by 5.92%, whereas the spring NDVI decreased by -5.82%. 16.46% and 15.49% of the study area showed a significant vegetation increase in summer and autumn respectively. Changes in vegetation growth in the West Liaohe River Basin may be affected by spring precipitation, summer temperature and precipitation and autumn temperature. The NDVI increase trends in the study area were related to the increased crop yield.