Digital capability is a powerful support for promoting farmers’ adoption of conservation tillage techniques, directly affecting rural industrial revitalization and the increase of farmers’ income. However, existing literature lacks research on how digital capability influences farmers’ adoption of conservation tillage techniques. Studies on the relationship between digital capability and conservation tillage techniques have mostly focused on mediating and moderating mechanisms, with insufficient research on the direct causal relationship between the two. This study draws on survey data from 1,633 farmers in Shaanxi and Gansu provinces. It employs the entropy method to measure farmers’ digital capability and uses the Ordered Probit model and mediation effect model to analyze the mechanisms through which digital capability influences farmers’ adoption of conservation tillage techniques. Empirical results show that digital capability significantly promotes farmers’ adoption of conservation tillage techniques. This core finding remains robust after replacing the core explanatory variable, replacing the core dependent variable, substituting the theoretical model, and excluding certain special samples. Mediation effect analysis indicates that digital capability enhances farmers’ adoption of conservation tillage techniques by improving their awareness of green agricultural production practices, reducing information search costs, and strengthening social trust. Heterogeneity analysis reveals that the effect of digital capability is more pronounced among farmers with more years of schooling and smaller cultivated areas. Farmers in regions with a higher share of agricultural income and a higher level of digital development are also more likely to adopt conservation tillage techniques. Compared to previous literature, this article has made certain extensions in the following aspects. Firstly, this article focuses on the digital capabilities of farmers themselves, exploring the role of digital capabilities in promoting the adoption of conservation tillage techniques from three aspects: digital information access, digital platform usage, and digital information acquisition. Secondly, based on the characteristics of farmers themselves, the research is carried out from three aspects: subject cognition, information cost, and social trust to clarify the mechanism by which digital capabilities help farmers adopt conservation tillage techniques. Third, it examines group-level heterogeneity by analyzing the differential effects of digital capability across farmers with varying levels of education, cultivated area, share of agricultural income, and regional digital development. This study, to a certain extent, reveals the inherent logic and mechanism of how digital capabilities help farmers adopt conservation tillage techniques. It can assist government departments in formulating differentiated subsidies and incentive designs for different groups of farmers to adopt conservation tillage techniques, providing hierarchical policy support for promoting digital construction in rural areas and accelerating rural digital development, and better helping farmers improve their digital capabilities and adopt conservation tillage techniques.