Purpose: The present study examined associations between the oral health behaviour (OHB) of Iranian mothers and the OHB and oral health status of their children. Materials and Methods: In 2005, two self-administered questionnaires provided data on the OHB of a random sample of 9- year-old children (n = 459) and their mothers in Tehran, Iran. Brushing frequency, use of fluoridated toothpaste and number of sugary snacks between meals served as oral self-care (OSC) assessment criteria for both. A clinical examination was performed for children at school. DMFT/dmft values, the restoration index (RI) and the unmet treatment needs index (UTN) facilitated an assessment of children's dental status and treatment. Chi-square test, bivariate correlation, and binary logistic regression model were employed in these analyses. Results: Mother's OSC correlated with child's OSC (r = 0.18; p 0.01). The reported children's brushing frequency correlated with mothers' brushing frequency (r = 0.2; p 0.01). High maternal OSC levels were associated with lower dental treatmemt (DT) values in children (p 0.01). Children's RI was positively and UTN negatively associated with mothers' OSC (p 0.01). In the model, mothers' OSC (OR = 2.1) and female gender (OR = 2.1) were associated with children's OSC, while mothers' OSC was strongly associated with DT (OR = 11.0) and RI (OR = 34.0) in children. Conclusions: Higher OSC levels of the surveyed mothers were reflected positively in the oral health status and behaviour of their offspring. The potential of mothers to play a significant role in the oral health of their children should be kept in mind when developing oral health promotion programmes. Keywords: child behaviour, dental health, maternal behaviour, oral health behaviour, oral self-care