Summary Introduction:?The oral breathing is a frequent symptom in childhood and has many alterations that compromise the child physical and cognitive development, negatively influencing from the oral breather, comparing her with the not oral breathers. Method:?Cross sectional study, prospective with a sample from 71 patients from 4 to 17 years, being 39 mouth breathers attended by otorhinolaryngologists and 32 patients not mouth breathers as the control group, evaluated as the quality of life through a questionnaire. Results:?The oral breathers presented more nasal problems, with the sleep and food, besides an greater average punctuation for snoring at night (p?