Abstract: Accuracy evaluation is the precondition and foundation for the application of land cover data. In order to study the ability of describing the land cover status in China, GLC2000, MODIS V004 and MODIS V005 land cover data on distribution area and spatial distribution were compared with the reference data in 2000 from RESDC (Data Center for Resources and Environmental Sciences, Chinese Academy of Science) based on land cover types aggregating. Land cover diversity index was introduced in this study to analyze the impact of land cover data accuracy. The results showed that: all the three data can describe the spatial distribution of land cover well in China; the precision of GL2000, MODIS V004 and MODIS V005 were 62.8%, 61.7% and 61.9% respectively; the proportion of forest/woods for the three land cover data were larger than that of reference data, the areas of building, wetlands and water bodies were smaller; the accuracy of forest/woods, grass/shrub lands, croplands and barren/ice were higher than that of urban and wetlands; the precise of forest/woods and croplands of GLC2000 were the most in provincial level, MODIS V005 has the highest user and producer accuracy on average; the precision of the three data were decreased with the increase of land cover diversity index, and it was increased with the increase of the proportion of land cover diversity index that equals to 1, land cover heterogeneity has the least impact on MODIS V005 data.