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This paper takes the Linxing area of the eastern margin of Ordos Basin as an example. Based on the data of reservoir fluid inclusions (FI) and combined with the history of buried thermal history in Linxing area, the main effects of magmatism on the gas accumulation time, accumulation period, gas accumulation dynamics and accumulation pattern are studied. The vitrinite reflectance (Ro) in source rocks of Zijinshan tectonic area is higher than that in gentle tectonic area. The closer to Zijinshan pluton, the more it tends to single period natural gas charging, the earlier time of gas charging. The characteristics of natural gas accumulation are evidently regional and zonal. Gas accumulation in gentle tectonic area conforms to the law of "gas accumulation in near source reservoir is earlier than remote source reservoir". The gas generated from the source rocks in the lower formation of the Zijinshan tectonic area reached the upper formation rapidly through the faults and fractures caused by the uplift of the Zijinshan pluton, and the accumulation interval time between the near source and remote source formation is relatively short. The Zijinshan tectonic area is the long-term high-pressure area and high-fluid potential area. The fluid potential in gentle tectonic area is low, and the fluid potential difference between the north and south is the motive force to promote the long distance lateral migration of gas. Zijinshan tectonic area is the hydrocarbon generation center and driving force source area, and gas accumulated rapidly from bottom to top. The features of gas accumulation in gentle tectonic area are dominated by vertical accumulation, supplemented by lateral supplementation. Since the Late Cretaceous, a large number of deep faults have been caused by the strong uplift of Zijinshan pluton, and a large number of natural gas are scattered through the faults and the reservoirs are destroyed. The faults in gentle tectonic area are not developed, and the natural gas preservation conditions are good, with good exploration prospects. • Although the role of Zijinshan pluton control of natural gas accumulation in the Linxing area has been noticed, it is limited to the representational description of the present phenomenon. It does not clarify the specific influence process and mechanism. In this paper, the inclusion analysis technique is mainly used to solve a series of problems of natural gas accumulation in the Linxing area under the action of magmatism. After studying the gas accumulation period, accumulation dynamics, and accumulation process, the characteristics of natural gas reservoir-forming in Linxing area are obviously regional and can be divided into the magmatic control area, the transition area, and the normal burial control area. [ABSTRACT FROM AUTHOR]