Introduction: School students are young adolescents who are in a period of acquiring good oral hygiene habits that are practised as they grow up. This study aimed to determine the association between oral health knowledge, attitude and practices (KAP) of the adolescents and their dental plaque maturity status. Methods: A cross-sectional study was conducted among 174 school students aged 13 to 14 years in Kota Bharu, Kelantan. The oral health knowledge, attitude and practices were assessed by self-administered questionnaires, while the dental plaque maturity status was assessed using GC Tri Plaque ID gel TM (TPID). The data were analysed using IBM SPSS version 24.0. Results: The mean (SD) for knowledge and attitude score of the students were 4.69 (1.44) and 3.63 (0.63), respectively. The mean (SD) dental plaque maturity score (DPMS) of the students was 1.02 (0.55). Students who had answered correctly on sugar and practised tooth brushing twice daily had significantly lower mean DPMS as compared to those who had answered incorrectly and practised tooth brushing less than twice daily (p<0.05). Conclusion: Adolescents participated in this study had moderate oral health knowledge and good oral health attitude. Correct knowledge regarding sugar and toothbrushing routines of at least twice a day significantly associated with the dental plaque maturity status.