To determine the influence of swimming on the incidence of otitis media in children, the authors designed a case control survey involving 32 children, aged 1 to 4 years, who were participating in swimming classes. Thirty control subjects were matched for age, race, and sex. The participants were pooled from the general pediatrics clinic and toddler swimming classes in Nassau County, New York. Parents completed a questionnaire gathering data over a 12-week study period during the winter months. Information was gathered regarding demographics, number of ear infections, history and frequency of swimming during the study period, presence of head submersion, day care center attendance, allergies, chronic medical conditions, otolaryngology consultations, ear surgery, and air travel. Forty-three percent of nonswimmers compared with 19% of swimmers had one or more ear infections during the study period (P < .02). The remaining factors surveyed did not differ significantly between groups. A review of the literature yielded two studies suggesting that swimming may have a beneficial effect on eustachian tube function and may indirectly decrease the occurrence of otitis media. Based on these findings, the authors conclude that there appears to be no basis to the commonly held belief that swimming may induce or exacerbate otitis media. In fact, the converse may be true.