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Fractional vegetation cover (FVC) is one of key indicators for the change of ecological environment. Estimation and analysis on regional FVC is of great significance for local government. In this paper, remote sensing technology was used to study FVC, and spatialtemporal FVC variation was analyzed from 1988 to 2013. Five periods of Landsat series remotely sensed data acquired in 1988, 1994, 2003, 2010 and 2013 were used to estimate the FVC based on topographyadjusted vegetation index (TAVI). TAVI can effectively eliminate the discrepancy between the shady and sunny slopes, and FVC calculated from TAVI can improve the estimation accuracy of the shady slopes. The vegetation coverage from 1988 to 2003 was generally well. The area percentage of FVC values which are larger than 06, were more than 65%, lying in the surrounding areas of the county. In most of the west and the north area, the FVC was larger than 08. The area percentage of FVC values less than 04 was less than 15%, mainly lying in the middle area along the Tingjiang River, which are also the most serious towns of soil erosion area. The worst FVC value occurred in 1994, which was decreased from 1988 and distributed in most of the towns, due to the serious frost occurred in the winter of the end of 1993 and the beginning of 1994. From 1994, the vegetation coverage was improved, and in 2003, the vegetation coverage recovered the level of that in 1988. From 2003 to 2013, the FVC was improved remarkably and most of the barren lands in the middle area are now covered with vegetation. The vegetation coverage has greatly been improved in the middle serious soil erosion towns particularly. The FVC changes are closely related to investment intensity for the control of soil erosion performed which was leaded by the local government. Due to the great efforts for treatment of soil erosion from 2000, a notable increase of FVC occurred from 2003 to 2013.