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MODIS NDVI time-series data could indicate vegetation status in each season and have been widely used for land cover classification and studies in the fields of vegetation and land degradation monitoring. During global land cover mapping project at 30m resolution aiming at developing high quality product, there were mistakes of classification between bareland and vegetation in GlobeLand30 data in regions surrounding deserts because that the dates of some images are not in growing season. In this paper, we proposed a method to check GlobeLand30 data of 2010 in these areas. Max NDVI value of MODIS NDVI time-series data is chosen to represent growing conditions of vegetation. And then vegetation fraction (VF) calculated from the max NDVI value is divided into bareland and vegetation based on the definition of bareland that VF of bareland is lower than 10%. The dimidiated VF maps are employed to check GlobeLand30 with the help of high resolution images and other references. Finally, errors found out by steps above are modified with VF maps and segmentation objects of images at 30m resolution. 149 map sheets of GlobeLand30 were checked and 105 of them were modified. 13409 samples in 10 map sheets totally were selected to assess the effect of the approach. The result showed that the accuracy after modification of GlobeLand30 was higher than that before modification.