Objective: To determine the prevalence of breath malodour and to assess the relationships between breath malodour parameters such as dental caries, habitual mouth breathing, tooth-brushing, and the frequency of upper respiratory-tract infection. Methods: A total of 628 healthy children (327 boys, 301 girls) ranging in age from 7 to 11 who were living in Kirikkale, Middle Anatolia, Turkey were included. Subjects who were taking antibiotics, having any suspicion of upper respiratory tract infection, sinusitis or tonsillitis at the time of survey were excluded from the study. Oral malodour assessment was carried out by organoleptic method. The DMFT/S was used to record caries. Pearson’s correlation coefficients were calculated to determine the association of each clinical variable to organoleptic oral malodour rating. Bivariate logistic regression analysis was performed to detect the degree of association between oral malodour and various dental-habitual parameters. Results: The prevalence of halitosis was 14.5%. Organoleptic oral malodour ratings were significantly higher in older age groups. Gender, frequency of tooth brushing, habitual mouth breathing did not influence oral malodour ratings. D(T), DMF(T), d(s) played the most significant role in higher oral malodour ratings, followed by d(t) and df(s). The frequency of tooth brushing, habitual mouth breathing did not contribute to the prevalence of halitosis:. Conclusion: Age, prevalence and severity of dental caries were significantly related to breath malodour. Key words: Breath malodour, dental caries, halitosis,. organoleptic rating.