Abstract: The time series of vegetation cover reflects the impact of climate change and human activities on the environment. To explore the variation characteristics of vegetation cover and its responses to climate and topography in Gansu Province, multiple methods such as the trend analysis, partial correlation analysis, and topography area correction were utilized to analyze the SPOT_NDVI time series data, as well as the meteorological and topographic data. It was found that, in the past 19 years, the vegetation cover in Gansu Province has recovered, however, there was largest areas with low vegetation cover. The spatial distribution of vegetation cover is generally high in the south and low in the north. It was found that vegetation cover was significantly positively correlated with precipitation in most parts of Gansu Province, especially in the Loess Plateau. In the humid regions of the south and the arid regions of the north, temperature promotes and inhibits vegetation growth respectively. In terms of topography, the semi-sunny slope area with an altitude of 2 500-3 000 m and slope of more than 25° is most suitable for vegetation growth. The study of vegetation cover is conducive to the planning of ecological construction and sustainable development. At the same time, it is of great theoretical and practical significance to the planning of human-land relations and economic development.