Background: Achievement of food security has become one of the major challenges of most developing countries, including Zimbabwe. This study was designed to investigate the effect of agricultural commercialization on household food security. Methods: This study used cross-sectional data for the 2017/18 farming season collected from 165 smallholder farmer households in Zhombe north rural district in Zimbabwe. Instrumental variable regression model was applied for data analysis over the effect of agricultural commercialization. Agricultural commercialization was measured using the crop output market participation share (COMPS). Results: The results revealed that COMPS, household head age, household head gender, and income per capita had a significant positive influence on household food security. Conclusions: The results indicate that agricultural commercialization and socio-economic characteristics have a role to play in defining the household’s food security. Therefore, the findings recommend policies that would promote agricultural commercialization, which improve household food security in turn. The study recommends policymakers to promote agricultural commercialization, since it positively contributed towards household food security. In addition, young-headed, female-headed, and low-income earning households that were identified as the food insecure households.