This study aims to evaluate the association between socioeconomic conditions and the lung function of children below 18 years old. Systematic review. PRISMA guidelines were followed to browse relevant studies from 2013 to 2023. Data from the included studies were extracted after the Newcastle-Ottawa risk of bias tool was applied. Forced expiratory volume in the first second (FEV1) liters. 20 papers with 89,619 participants were included. Logistic regression model for FEV1 based on multiple SES indices, suggested a positive association between lower respiratory function and a lower SES, with an interquartile odds ratio (OR) of 1.67 (95% CI 1.03-1.34). Children from a lower socioeconomic status (SES) do exhibit lower lung function and addressing the causes of this can contribute to developing preventive public health strategies. Lack of appropriate reference values and varied indicators of socioeconomic status in the studies contributed to significant statistical differences. CRD 42020197658.