[Objective] The temporal and spatial dynamic changes of desertification in the Kubuqi Desert during 2000—2023 were investigated, aiming to provide theoretical references and basic data support for the restoration of vegetation and ecological construction. [Methods] Based on the features of Landsat remote sensing images, the spatial and temporal distribution and change trend of land desertification in the Kubuqi Desert and its surrounding areas from 2000 to 2023 were studied by using enhanced vegitation index (EVI) remote sensing index gray segmentation, land desertification degree classification, land use dynamic attitude, abundance index and importance index. [Results] The total desertification area in the Kubuqi Desert decreased from 10 694.6 km² in 2000 to 8 837.56 km² in 2023. The area of extreme desertification was reduced from 6 272.11 km² to 1 461.15 km², that of severe desertification increased from 1 773.97 km² in 2000 to 2 874.48 km², of moderate desertification increased from 1 372.16 km² in 2000 to 1 965.84 km², and of mild desertification increased from 1 276.35 km² to 2 535.58 km². Considering the perspective of time series, the rate of extremely severe desertification from 2000 to 2023 was 3.33%, that of severe desertification was 2.70%, of moderate desertification was 1.88%, and of mild desertification was 4.29%. The area of extremely severe desert land types decreased from 6 272.11 km² in 2000 to 1 461.65 km² in 2023, with a total loss area of 4 949.72 km². From the spatial perspective, the distribution of extremely severe desert types changed from distributed over time to concentrated, becoming dominant from 2000 to 2010; the multiple-degree index of severe and moderate desertification types ranged between 7.69% and 16.15%, indicating that the long-term distribution of heavy and moderate desertification types was concentrated; mild desertification types were scattered and extensive over time. [Conclusion] From 2000 to 2023, the area of Kubuqi Desert showed a decreasing trend, and the ecological environment had been improved. In the future, the ecological restoration of this region will focus on the extremely severe desert area.