Objective: To establish the role of various risk factors for otitis media among preschool, rural Indian children. Methods: A cross sectional study of 800 children was undertaken to determine the prevalence of otitis media. Thereafter, using a case control study design, all the cases and an equal number of controls were compared in terms of various common risk factors for otitis media. The 13 risk factors studied were age, sex, socioeconomic status (SES), nutritional status, balwadi attendance, duration of breast feeding, passive smoking, exposure to household smoke, persistent rhinorrhoea,positive throat culture, snoring, seasonal rhinitis and allergic rhinitis. Bivariate association between these risk factors and otitis media was studied using chi-square test of proportions. Multivariate logistic regression analysis was done by including the variables which were significant at p = 0.35 in the bivariate analysis. Results: From the cross sectional study, the prevalence of otitis media was found to be 8.6%, roughly half the prevalence obtained 10 years previously from the same region. Otitis media with effusion (OME) was the commonest manifestation of otitis media (6%) with 3.8% having bilateral disease. Ear wax was seen in 27.5% of subjects. Eighteen (2.3%) children failed the screening audiometry test set at 40 dB HL. Sociodemographic factors among cases and controls were comparable. The prime risk factors for otitis media identified by bivariate analysis included persistent rhinorrhoea, snoring and seasonal rhinitis. On multivariate logistic regression analysis, persistent rhinorrhoea (p < 0.01,O.R. = 7.56, 95%C.I. 2.73 - 20.92), snoring (p = 0.01,O.R. = 4.89, 95% C.I.1.32 - 18.17), seasonal rhinitis(p = 0.02, OR = 5.93,95% CI = 1.33-26.51) and passive smoking (p = 0.04, O.R. = 3.29, 95%C.I. 1.05-10.33) were found to be important risk factors for otitis media. Age, sex, SES, parental education, seasonal or allergic rhinitis, inadequate breast feeding and exposure to household smoke were not significant risk factors. Conclusions: Otitis media continues to have a high prevalence among South Indian children. Persistent rhinorrhea. snoring, seasonal rhinitis and passive smoking are the chief risk factors for the disease. Measures to reduce the prevalence of otitis media by addressing these risk factors are urgently required. (C) 2010 Elsevier Ireland Ltd. All rights reserved.