Objectives: To assess oral health behaviour & self-practice among HBS undergraduate medical & dental students in Islamabad, Pakistan & to evaluate the variations in oral health behaviour & self-practice based on age, gender, academic program (MBBS/BDS) & education year.Methods: Hiroshima University Dental Behaviour Inventory (HU-DBI) questionnaire in English version consisting of 20 dichotomous responses (Agree/Disagree) was self-administered among 300 undergraduate medical & dental students of HBS Medical & Dental College in Islamabad. Three hundred medical and dental students were selected by convenience sampling. This cross-sectional study was conducted in the month of October 2019 & 38 questionnaire forms were excluded from the study which was incomplete & data was analysed on 262 (51 from dental & 211 from medical students) student's responses using SPSS Version 24 and statistical significance was set at P < 0.05.Results: The mean age of students who participated in the study was 21.26 ± 1.90 years with a total number of 109 males & 153 females. A significantly higher HU-DBI score was observed among students from higher years of education only (p-value of 0.015). The majority of students (80.1%) brush their teeth daily. About 64.5% of students mentioned that they use toothbrushes & 15.6% used miswak on daily basis for cleaning their teeth. About 88.6% of students did not use mouthwash & toothpicks regularly.Conclusion: It can be concluded from the results that students belonging to higher years of education showed improved oral health behaviour and attitude as compared to the early years of education. Overall health behaviour observed was adequate.