The study investigates the relative importance of supply-side and demand-side factors of household food security through a logistic regression analysis applied to data collected from 247 sample households in Southern Ethiopia. Among the nine factors included in the model, seven were identified as statistically significant determinants of household food security: technological adoption, farming system, farm size, land quality, household size, per capita aggregate production and access to market. Among these, technological adoption, farming system, farm size, and land quality are supply-side factors. Household size, per capita aggregate production, and access to market are demand-side factors. Based on the magnitude of their partial effects on the probability of food security, supply-side factors are more powerful than the demand-side factors in determining household food security, implying that interventions focused on these factors need to get priority attention by policy, research and extension.