Purpose: The aim of this study was to investigate the association between cognitive and behavioural factors of preadolescents and those of their mothers, assessed in terms of self-efficacy beliefs and toothbrushing among Turkish and Finnish population in the framework of Social Cognitive Theory. The specific objective was to test if this possible association worked regardless of cultural differences. Materials and Methods: Self-administered questionnaires for Finnish (n = 338) and Turkish (n = 611) pre-adolescents and their mothers were used to collect the information on cognitive (pre-adolescent and maternal self-efficacy) and behavioural factors (toothbrushing frequencies). Results: Turkish mothers and pre-adolescents reported lower levels of self-efficacy and toothbrushing than did their Finnish counterparts (P 0.005). Finnish pre-adolescents reporting high self-efficacy were more likely to have mothers with high levels of self-efficacy (OR = 2.14, 95% CI = 1.16 to 3.93), (P = 0.014). Similar positive associations emerged between Turkish (OR = 2.45, 95% CI = 1.70 to 3.52), (P = 0.001) and Finnish (OR = 6.76, 95% CI = 2.21 to 20.65), (P = 0.001) pre-adolescent self-efficacy and maternal recommended (twice daily) level of toothbrushing behaviour. For pre-adolescents' toothbrushing, their own self-efficacy was the common explanatory variable. Binary logistic regression models revealed that the maternal toothbrushing accounted for the Turkish pre-adolescents' toothbrushing behaviour, whereas maternal self-efficacy did so for the Finnish pre-adolescents' (P 0.001) toothbrushing behaviour. Conclusions: This study underlines the need for integration of pre-adolescent self-efficacy and maternal cognition and behaviour into oral health intervention programmes because of their relation to recommended toothbrushing behaviour among pre-adolescents, regardless of cultural differences. These findings seem to fit with the Social Cognitive Theory, which emphasises the significance of cultural factors and cognition as the determinants of behaviour. Keywords: culture, maternal, mothers, oral hygiene, pre-adolescent, self-efficacy, Social Cognitive Theory, toothbrushing behaviour