Goal two of the 17 Sustainable Development Goals by the United Nations aims to achieve ‘zero hunger’. Six of the eight targets of the ‘zero hunger’ goal are directly or indirectly related to agriculture. Of these, Target 2A in particular, focuses on increasing investment in agriculture. Little empirical evidence exists to date to justify meeting this target through increased expenditures on agriculture. This study analyses a global dataset to examine the impact of public agricultural expenditure on food insecurity for sixty low- and lower-middle income countries for 1990−2014. Public agricultural expenditure is defined as the share of public expenditure on agriculture in total public expenditure. Food insecurity is measured through undernourishment prevalence and food deficit depth. The results of the study reveal that an increase in the share of agricultural expenditure in total public expenditure significantly reduced hunger in low and lower middle-income countries during the study period. These results are robust to alternate estimation techniques and various definitions of public agricultural expenditure. The favourable effect of public agricultural expenditure on food security in low income and lower-middle income countries underscores the significance of public support to agriculture and implies that such support should continue and grow in these nations given their high prevalence of food insecurity.