Desert oases are critical for biodiversity maintenance, water conservation, and agriculture in desert ecosystems. These critical habitats face significant threats due to global changes in climate and land-use. In response, China has implemented ecological water conveyance over several decades, yet there remains a paucity of comparative assessments on the effectiveness of these interventions, particularly concerning the succession of oasis vegetation with and without water conveyance. In this study, we evaluate the succession dynamics of their riparian oases from 1980 to 2020, focusing on the Hotan River basin (with water conveyance since 2001) and the Keriya River basin (without water conveyance) in Taklimakan desert, northwestern China. We analyzed vegetation changes in relation to distance from the river channel, distance from the river source, and relative height to the riverbed using spatiotemporal dynamic data. Water conveyance alleviated the degradation of vegetation in Hotan River. Comparing with Keriya River basin whose vegetation degraded in the decades, our results reveal a positive vegetation succession in Hotan River basin. The water conveyance promoted the expansion of herbs in the first five years, the vegetation progressed toward advanced successional stages from the 5th to 10th years, especially for shrubs at the zone 4 to 6 m away from the river, and the vegetation distribution increased 2 m in altitude. These changes decreased during the last ten years of water conveyance. Our results reveal that vegetation succession in the desert oases is driven by water availability, with proximity to the river and elevation being key factors. Water conveyance has improved vegetation, but after a decade, progress plateaued. Future efforts should focus on increasing water supply and adjusting river morphology, concerning the altitude differences, to enhance restoration.