The adoption of chemical fertilizer technologies is crucial for sustainable economic development. The relation of chemical fertilizer technology adoption decision and food security of agricultural sector has been poorly understood. Therefore, this study attempts to investigate the factors affecting adoption decisions and their impact on food security in southern Ethiopia using cross-sectional survey data gathered in 2019/20. A field survey was collected among 382 smallholder farmers in the Soro district. Descriptive statistics and econometric methods such as probit regression, Heckman two stage-method, and propensity score matching were employed for the data analysis. The results of probit regression showed that the technology participant was significantly affected by education status, size of family, family labor, livestock holding, credit service, extension service, agricultural technology information, distance to market, distance to road, and non-farm activity. Adoption was associated with a significantly higher crop yield and expenditure. The findings suggest that the role of technology adoption at the farm level due to higher yield and income could lead to reduced poverty. The results suggest that the role of chemical fertilizer technology adoption in improving household food security among smallholder farmers results mainly in higher cereal crop yields and incomes.