OBJECTIVE: To investigate the relationship between socio-economic and oral habits (HO) in mouth breathing children (RO) Method: The sample consisted of 13 children, eight boys and five girls. In anamneses, asked about the psychomotor development, health problems, dietary, HO, sleep, and median family income. HO was considered prolonged bottle feeding, pacifier and / or finger sucking for a period not less than three years. We classified the breathing mode through anamnesis and the usual position of the lips during speech screening. Is tabulated data for later analysis in Excel specification. The information used in this study is part of a project approved by the Ethics Committee of the UFSM. Results and CONCLUSIONS: 61.53% of the sample were boys and 31.47% girls, mean age of 8.7 years. In this sample, 76.92% and 23.08% had HO not. With regard to family income, 15.38% had up to minimum wage (G1), 69.24% up to three (G2), 7.69% for up to five (G3) and 7.69% up to 15 minimum wages (G4). As for family income and the presence of HO in G1 50% of the sample had HO and the other half did not, now G2, 77.78% of the children had HO and 22.22% did not. In G3 and G4 prevalence was 100% for the HO. Showed a prevalence of OH in RO, corroborating with the literature. The socioeconomic profile, it was found that most families with incomes up to three minimum wages, and this group was higher prevalence of HO.