Aim To evaluate the relationship between children's perception of caries and gingivitis and their oral health behaviours. Design Participants in this cross‐sectional study were children aged 11–14 years. A questionnaire for measuring children's perceptions and behaviours was developed, validated and applied. Perceptions were analysed as predictors for behaviours using multiple logistic regression analysis. Results A total of 434 children (57% males) participated in the study. Half of them perceived caries as a disease and believed in visiting the dentist regularly regardless of dental need. More than 60% were unaware that gum bleeding is a sign of disease and only 60.7% believed that it requires a management. Being aware that gum bleeding is a sign of disease and that it requires treatment increased the odds of brushing 2.83 (OR = 2.83, 95% CI:1.33–6.12) and 2.1 (OR = 2.1, 95% CI:1.05–5.55) times, respectively. Children aware of importance of dental visits even without dental decay were 2.9 times more likely to visit the dentist regularly (OR = 2.86, 95% CI:1.25–5.75) and were 77% more likely to never miss a dental appointment (OR = 1.77, 95% CI:1.03–3.37). Conclusion Being aware that bleeding gum requires treatment was a determinant of toothbrushing habit. Improved perceived need for dental check‐up regardless of dental problem may promote children's preventive dental attendance.