This paper explores the contribution of social capital on the rural household food security. Social capital is the ability of community actors to secure benefits by virtue of membership in social networks or other social structures. Consensus has emerged among scholars that social capital can contribute significantly to the alleviation of poverty. Food insecurity is an indicator of poverty. Using the Malawi case study, this paper investigates the role of social capital on the food security in developing countries. Household survey data were used to incorporate different social capital variables into the household welfare model, controlled by human capital, physical capital, household and geographical characteristics. Household food security status was improved by membership to farmers’ organizations, household network size and engagement in voluntary activities. When all social capital variables were incorporated into the models the explanatory power of the model improved by 11 and 20% on household income and food security respectively. We conclude that social capital has positive influence on household food security; however, the effects vary depending on the nature of social capital. The results indicate the significance of social networks in improving the socio-economic livelihoods of the people in rural areas in developing countries.