Objective: To evaluate the association of food insecurity with demographic and socioeconomic conditions in households in Campinas, São Paulo state, Brazil. Methods: This is a cross-sectional study conducted on a representative sample of the urban population of the Southern, Southwestern, and Northwestern Health Districts of Campinas, between 2011-2012. Characteristics of the head of household, family history and household patterns were investigated. The dependent variable was food security condition, categorized as food security, mild food insecurity, and moderate/severe food insecurity. All independent variables with p-value <0.20 in the bivariate multinomial logistic regression were included in the final model of multiple multinomial logistic regression, adjusted to household head age; the remaining variables had p-value <0.05. Results: In the 691 households analyzed, there was 65% of food security, 27.9% of mild food insecurity, and 7.1% of moderate/severe food insecurity. The conditions associated with mild food insecurity were monthly per capita income less than the minimum wage, household head unemployed for more than six months between 2004-2010, living in properties given to the family/occupied/other, and density higher than two people per bedroon. The moderate/severe food insecurity was associated with informal employment condition of the household head and the presence of a beneficiary of the Bolsa Família (Family Allowance Program), a cash transfer-type program, in the household. The higher the score of the consumer goods, the lower the probability of mild food insecurity or moderate/severe food insecurity. There was a higher probability of mild food insecurity and moderate/severe food insecurity in unfinished masonry-built houses/other. Conclusion: More than one third of the households investigated experienced some form of food insecurity. Mild food insecurity was associated with demographic conditions, while moderate/severe food insecurity was associated with socioeconomic conditions, especially those related to the household head.