It is of significance to monitor the changes in vegetation in the assessment of regional ecological environment quality and ecological process. The typical Hotan Oasis in the arid region of Northwestern China was selected as the study area. Based on Landsat remote sensing images, the temporal and spatial changes in the vegetation cover in Hotan Oasis were analyzed using NDVI, binary dichotomy, and gravity center migration models. The aim of this study was to understand the characteristics of vegetation cover changes in the oasis during recent decades. The results demonstrated that the vegetation distribution in Hotan Oasis is generally distributed from high to low on the axis of Yulongkash and Karakash Rivers. The high vegetation cover is concentrated in the middle of the oasis, whereas, the high vegetation is surrounded by relatively the low and medium vegetation. During the past 23 years, the vegetation-covered area and vegetation coverage of Hotan Oasis have increased significantly. In 2016, compared with that in 1994, the vegetation-covered area has increased by 553 km², an increase of 19.6%. In terms of different levels of vegetation cover changes, high vegetation cover increased significantly, with an increase of 897 km² (83.6%) during the past 23 years. The fluctuation and change in medium vegetation cover were obvious. In 2016, compared with that in 1994, the area decreased by 103 km² (9.3%); low vegetation cover significantly reduced, with a decrease of 241 km² (38%) during the past 23 years. There are time-phased and regional differences in the spatial changes in the coverage of Hotan Oasis. In terms of area change, from 2000 to 2005, the area of oasis vegetation cover increased most obviously. In terms of regional changes, the vegetation coverage in the west and east of the oasis increased most significantly, and the urban areas and nearby areas of Hotan City, Moyu County and Lupu County decreased significantly. The expansion of cultivated land is the main cause of changes in oasis cover. However, the reclamation of natural grassland will reduce the ecological effects of the oasis, which will threaten the ecological stability and sustainable development of the oasis in the long term. As a whole, over the past 23 years, the center of gravity of oasis cover has moved westward.