The paucity of literature on the influence of land tenure across a range of food insecurity outcomes may impede a complete analysis in developing countries. This paper examines the association between land tenure and food security among 1434 sampled smallholders from the Nigeria Living Standards Measurement Study-Integrated Surveys on Agriculture (LSMS-ISA) three-round panel dataset. The data were analyzed by a flexible conditional difference-in-difference model and a generalized ordered logit regression. The regression results showed that smallholders who owned land and acquired plots for free were less likely to have high Household Dietary Diversity Scores (HDDS). On the other hand, owners of family-inherited plots were more likely to consume diverse diets and hold more assets. Holders of informal land documents were more likely to be food secure by having a low food expenditure share, high HDDS and Livelihood Coping Strategy (LCS). Meanwhile, perceived rights to mortgage land for a loan may be enhanced with having formal land certificates than informal land documents. The study concluded that formal land governance should recognize land ownership via family inheritance and holding informal land documents to support smallholder food security by increasing their dietary diversity and lowering their food expenditure shares.