Emerging body of knowledge suggest the need for food expenditure studies in the urban areas. This study identified the determinants of food expenditure among urban households in Lagos Mainland Local Government Area of Lagos State, Nigeria. Respondents (household heads) were selected randomly and data gathered by means of structured questionnaire. Data analysis was accomplished using descriptive statistics and regression model. Results of the study showed that 60% of the household income was expended on food which is considered high, suggesting low income and possible high cost of food in the study area. When combined with existing large members (>5) in most households (66%), existence of food insecurity and vulnerability to poverty in the study area was implied. Regression analysis showed that 65.5% of the variation in household expenditure on food in the study area was accounted for by the explanatory variables. Household income, tribe, household size and the composition of the household had a significant effect on food expenditure. The authors, therefore, recommended a policy option for general food price subsidy and particularly to address urban food prices which would improve spatial pricing efficiency.