[Objective] To explore the temporal and spatial variation and influencing mechanism of soil moisture in different ecological zones of Ningxia, so as to provide a basis for ecological construction and optimal management of water resources in Ningxia, and better serve the ecological protection and high-quality development strategy of Ningxia. [Methods] Ningxia Hui Autonomous Region was selected as the study area,this article is based on the annual average dataset of soil moisture reanalysis data from 2003 to 2022 by remote sensing inversion method, as well as meteorological, vegetation cover NDVI, land use, and other data. Trend analysis, mutation testing, and Hurts index are used to analyze the spatio-temporal changes and future trends of soil moisture in different zones of Ningxia over the past 20 years. The impact mechanism of soil moisture changes is explored based on the optimal parameters with geographic detector. [Results] ①Over the past two decades, the annual average soil moisture across Ningxia Autonomous Region has exhibited a significant upward trend overall, with the area experiencing an increase in soil moisture (68.99%) being substantially larger than that experiencing a decrease (31.01%). From the perspective of different subregions, the spatio-temporal distribution of soil moisture is uneven, and there are notable differences in the trends of change. Specifically, the Yellow River Irrigation Area in the north shows a slow downward trend, albeit insignificant, with an annual average decrease in soil moisture by 0.010cm^3/cm^3. The arid zone in the central region demonstrates a slow upward trend, also insignificant, with an annual average increase in soil moisture by 0.005cm^3/cm^3. The mountainous area in the south exhibits a significant upward trend, with an annual average increase in soil moisture by 0.049cm^3/cm^3. Furthermore, a mutation test reveals a significant mutation in 2012, marking a substantial acceleration in the rate of increase. Regarding the spatial distribution pattern of soil moisture, it displays a characteristic of "high in the north and south, low in the center". The multi-year average soil moisture, from highest to lowest, is as follows: the Yellow River Irrigation Area in the north (0.114cm^3/cm^3) > the mountainous area in the south (0.107cm^3/cm^3) > the arid zone in the central region (0.084cm^3/cm^3).②The future trend prediction based on the Hurts index shows that about 49.09%, 60.43%, and 62.91% of the areas in the northern Yellow River irrigation area, central arid zone, and southern mountainous area, respectively, showing a decreasing trend in soil moisture changes (the area with proportion of continuously decreasing and from increasing to decreasing), while about 51.18%, 39.57%, and 37.09% of the areas showing an increasing trend (the area with proportion of continuously increasing and from decreasing to increasing). The soil moisture changes in the continuously increasing and decreasing regions, especially in the northern Yellow River irrigation area and central arid zone, should be given continuous attention to prevent salinization and drought disasters .③According to the analysis of the optimal parameter geographic detector, the main influencing factors of soil moisture distribution in Ningxia are NDVI and terrain, followed by precipitation and land use changes. Moreover, over time, the impact of precipitation on soil moisture in different zones of Ningxia gradually increases. [Conclusion] In the past 20 years, the trend of soil moisture change in Ningxia has shown certain regional differences and complexity, and the change of soil moisture in the future will also show significant regional differences. At the same time, NDVI, topography, precipitation and other factors jointly affected the distribution of soil moisture in Ningxia. Therefore, the influence of these factors should be fully considered when formulating scientific and reasonable soil resource management and protection strategies, so as to ensure that Ningxia's ecological construction and optimal management of water resources can provide a basis and better serve the healthy development of the ecological environment.