This cross-sectional national survey aimed to determine the prevalence of oral and hand hygiene practices as well as associations between sociodemographic characteristics and oral and hygiene practice among adolescents aged 13 to 17 years during the past 30 days. A validated self-administered bilingual questionnaire adapted from the Malaysian Global School Health Survey with computer-scanable answer sheets was distributed to 30 823 adolescents attending government secondary schools in Malaysia; and 89.2% responded to the questionnaire given. More than 80% (87.1%; 95% confidence interval [CI] = 86.24-87.96) of the adolescents reported that they had brushed their teeth at least twice daily and had always washed their hands after using the toilet (86.6%; 95% CI = 85.85-87.36). The odds of adolescents who brushed their teeth at least 2 times daily and washed their hands after using the toilet was significantly associated with sociodemographic characteristics. This study highlights the need to further improve the effectiveness of current oral health promotion programs with consideration for sociodemographic characteristics.