Abstract: Coastal saline-alkali areas represent a crucial non-traditional farmland resource for ensuring stable and increased grain production. However, the abandonment of farmland hinders agricultural development and sustainable utilization. Uncovering the spatio-temporal evolution characteristics and driving mechanisms of farmland abandonment in these areas provides scientific support for the efficient use of non-traditional farmland resources and the national strategy of ensuring food security. Focusing on the Yellow River Delta in Shandong Province as the study area and utilizing remote sensing datasets on land use from 2000 to 2024, this study employs annual land-use trajectory tracking, natural environmental gradient analysis, and multiple linear regression to analyze the spatio-temporal patterns, duration, environmental associations, and comprehensive driving factors of cultivated farmland abandonment in coastal saline-alkali regions. The results showed that: 1) From 2000 to 2024, the farmland area in the Yellow River Delta continued to decline, while farmland abandonment exhibited an overall fluctuating upward trend. The cumulative abandoned farmland area reached 11.32•10⁴ hm². Spatially, abandoned farmland was mainly concentrated in the northern Yellow River Delta and along the Bohai Sea coast, showing distinct coastal clustering and continuous accumulation. 2) The duration of farmland abandonment gradually decreased from coastal areas to inland areas, and the abandoned area declined with increasing abandonment duration. Short-term abandonment within five years dominated the study area, indicating that most abandoned farmland had not yet entered a long-term stable abandoned state. However, within Dongying City, Hekou District, Zhanhua District, and Kenli District had relatively large areas of farmland abandoned for more than 10 years, suggesting a pronounced long-term and fixed abandonment pattern in these areas. 3) Low-lying coastal conditions and salinity stress constituted important natural foundations for farmland abandonment. Abandoned farmland tended to occur in environmentally sensitive areas with elevations below 200 m, slopes of 0°-1°, and distances within 30 km from the sea, accounting for 98.83%, 97.98%, and 83.76% of the total abandoned farmland area, respectively. In addition, 81.77% of abandoned farmland was located in soil salinization areas, indicating that saline-alkali stress imposed a strong constraint on the stability of farmland use. 4) Farmland abandonment in the Yellow River Delta can be interpreted as a process of farmland marginalization and withdrawal jointly driven by natural environmental constraints, farming condition limitations, and socioeconomic transition in coastal saline-alkali areas. Improvements in farmland contiguity, irrigation guarantee capacity, and agricultural mechanization significantly inhibited farmland abandonment by enhancing land-use stability and reducing farming costs. Per capita GDP and per capita disposable income of rural residents were positively correlated with abandoned farmland area, suggesting that economic development and non-agricultural employment opportunities may increase the opportunity cost of agricultural labor and weaken the willingness to continue cultivating low-efficiency farmland. In contrast, farmland area per capita had a significant negative effect on farmland abandonment, indicating that better farmland resource endowment is conducive to moderate-scale farming and abandonment risk reduction. This study will further enrich theoretical understanding in agricultural geography and land system science, while providing scientific support for the conservation of cultivated land resources, the comprehensive utilization of saline-alkali land, and regional agricultural governance in coastal saline-alkali areas.