Sustainable land management (SLM) practices are important for tackling agricultural land degradation. This study investigates the association between farmers’ time preferences and their adoption of SLM practices (agroforestry, terracing, and land fallow practices) with intertemporal benefits, and further documents the moderating role of land tenure security in this relationship. The analysis in the paper is based on data from a survey of 480 farmers in south-east Nigeria, complemented by semi-structured interviews. Farmers’ time preferences were elicited using both a survey and experiments with hypothetical payouts. Land tenure was conceptualised as a composite concept to suit the legally pluralistic context of the study area. This study found that many of the sampled farmers have high discount rates. The result further shows that farmers’ time preferences are negatively associated with their adoption of agroforestry and land fallow practices. Moreover, the result shows that both legal and de facto tenure security encourage the adoption of SLM practices. Other factors influencing the adoption of SLM practices include gender, household size, education, credit constraints, marital status, risk attitude, farming experience, and farm characteristics (e.g., erosion problems and steepness of slope). Furthermore, this study found that the security-enhancing effect of land tenure security (de facto) can alleviate the negative influence of time preferences on farmers’ adoption of SLM practices. The findings suggest that farmers with higher discount rates, who have secure tenure rights to land, are more likely to adopt SLM practices, compared to similar farmers without tenure security.