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The main purpose was to explore the spatialtemporal changes of farmland in Luntai Artificial Oasis in Dina River Watershed, aiming to provide basic data and theoretical basis for the spatial planning and management of artificial oasis in small watershed. The land use information of farmland was extracted from the remote sensing images（obtained in August 1992, August 1998, September 2007 and August 2018）and unmanned aerial vehicle data（obtained in July and August 2018 in the field survey）by means of visual interpretation supported by RS and GIS, and analyzed via mathematical statistic, dynamic degree, transfer matrix and gravity center model. Results showed that the area of farmland in Luntai Artificial Oasis was increased from 8381hm2 in 1992 to 46284hm2 in 2018. In 1992, totally 40.18% of artificial oasis was occupied by farmland, which was decreased to 37.04% in 1998, and then followed by a long time increase to 71.28% in 2018. In 1992, totally 1.61% of watershed area was occupied by farmland, which was increased to 8.91% in 2018. The area of farmland in Luntai Artificial Oasis was developed rapidly and experienced three stages: the stage of moderate increase（1992—1998）which was driven by reclamation policy launched by local government with annual average growth rate of 2.28%; the stage of rapid increase （1998—2007）which was influenced by both the cotton industry and reclamation policy with annual average growth rate of 16.85%; and the stage of moderate increase（2007—2018）which was only influenced by cotton industry with annual average growth rate of 846%. In the past 26 years, the land that was transferred into farmland（41545hm2）was far more than the land that was transferred out（3441hm2）. The land outside artificial oasis（35179hm2）was the main source supporting the extension of farmland. The land that transferred out of farmland was mainly into the forestry and fruit industry（2671hm2）. The gravity centers of farmland was gradually moved in the direction of sandy desert because the exploration and maintenance cost of sandy desert was lower than that of Gobi desert, and the cotton which was the most popular crop in Luntai Artificial Oasis had adapted to the atmosphere of the oasissandy desert transition zone in Dina River Watershed.