Background: Oral health behaviour established during young adulthood significantly influences long-term dental outcomes. Despite increased awareness, preventive practices remain inconsistent.

Aim: To assess knowledge, awareness, and oral health behaviour among patients aged 18–25 years.

Materials and Methods: A descriptive cross-sectional study was conducted among 250 patients aged 18–25 years attending a dental outpatient department. A structured and validated questionnaire assessed demographic characteristics, oral hygiene practices, knowledge of oral diseases, adverse habits, and dental visit patterns. Data were analyzed using SPSS version 25.0. Descriptive statistics were expressed as frequencies and percentages. Chi-square test was applied to determine associations between variables. Statistical significance was set at p < 0.05.

Results: Among 250 participants, 145 (58%) were females and 105 (42%) were males. Brushing twice daily was reported by 72%, while 28% brushed once daily. Fluoride toothpaste use was 81%, floss usage 25%, and mouthwash use 38%. Regular dental visits (every 6–12 months) were reported by 46%, whereas 54% visited only during pain. A statistically significant association was found between gender and brushing frequency (χ² = 6.84, p = 0.009), and between educational level and fluoride toothpaste use (χ² = 8.21, p = 0.004).