Objective Food insecurity (FI) is a major public health problem in Lebanon, a small middle-income country with the highest refugee per capita concentration worldwide and prolonged political and economic challenges. The present study aimed to measure the prevalence and sociodemographic correlates of household FI and to explore the association of household FI with anthropometric measures of children and their mothers. Design Cross-sectional survey (2014-2015). Setting Lebanon. Participants Nationally representative sample of Lebanese households with 4-18-year-old-children and their mothers (n 1204). Results FI prevalence (95 % CI), measured using the Arabic-translated, validated Household Food Insecurity Access Scale, was found to be 49 center dot 3 (44 center dot 0, 54 center dot 6) % in the study sample. Mild, moderate and severe FI were found in 7 center dot 0 (5 center dot 5, 9 center dot 2) %, 23 center dot 3 (20 center dot 1, 26 center dot 8) % and 18 center dot 9 (14 center dot 9, 23 center dot 5) % of households, respectively. Multiple regression analysis showed that low maternal and paternal education, unemployment and crowding were significant correlates of household FI (P<0 center dot 05). No significant associations were observed between FI and anthropometric measures of children and their mothers, after adjusting for other socio-economic correlates. Food-insecure households reported various mechanisms to cope with food shortage, such as reducing the number of meals/d (49 center dot 6 %), borrowing food (54 center dot 4 %), spending savings (34 center dot 5 %) and withdrawing children from schools (8 center dot 0 %). Conclusions FI exists among a remarkable proportion of Lebanese households with children. Correlates of household FI should be considered when designing social welfare policies and public health programmes to promote more sustainable, resilient and healthier livelihoods among vulnerable individuals.