Introduction The development of agricultural mechanization is a crucial pathway to promoting agricultural modernization and holds significant importance for improving the eco-efficiency of cultivated land use.Methods The super-efficiency SBM model is employed to gauge cultivated land use eco-efficiency in this research, which selects 90 prefecture-level cities across the Yellow River Basin during 2013-2023 as its research sample. The impact mechanism and spatial spillover effects that agricultural mechanization has on cultivated land use eco-efficiency are empirically inspected by means of two-way fixed effects models, mediation effect models, and moderation effect models in the next research phase.Results The results indicate that the eco-efficiency of cultivated land use in the Yellow River Basin exhibits an overall fluctuating upward trend. Agglomeration of the high-high type is primarily allocated to the lower reaches, whereas the middle reaches mainly concentrate agglomeration of the low-low type. Agricultural mechanization exerts a marked promotional effect on cultivated land use eco-efficiency. Mechanization improves eco-efficiency mainly through pathways such as large-scale land management and precision fertilization. Fiscal empowerment positively moderates the eco-efficiency of cultivated land use. The promoting effect of agricultural mechanization is more pronounced in the middle reaches of the Yellow River Basin as well as in semi-arid and semi-humid areas. Moreover, agricultural mechanization can significantly enhance the eco-efficiency of cultivated land use in neighboring regions through positive spatial spillover effects.Discussion Therefore, it is essential to optimize the agricultural machinery extension system, promote mechanization tailored to local conditions, activate key impact pathways, strengthen positive spatial spillover effects, and collaboratively improve the eco-efficiency of cultivated land use.