Introduction: Despite it being culturally forbidden, youth are voluntarily engaging in premarital sex which could lead to poor sexual behaviour in adult life. This nationwide study aimed to determine the prevalence of permissive attitude towards premarital sex among young university students and its associated factors. Methods: A cross-sectional study was conducted from June 2021 to December 2021 among students attending higher education institutions in Malaysia using stratified random sampling. A self-administered online questionnaire was used that captured participants’ sociodemographic characteristics, knowledge of sexual health, childhood abuse, and attitudes toward premarital sex. Data were analysed using SPSS 27. Results: Out of 1171 respondents, 42.4% have demonstrated permissive attitude towards premarital sex. Half had adequate knowledge on sexual health (50.2%). Among the four types of childhood abuse, only emotional abuse (p=0.02) was found more likely (AOR: 2.01; 95% CI: 1.30-3.12, p=0.02) to have permissive attitude towards premarital sex. Being a Muslim (p<.001) and living in urban area (p=0.03) were protective factors against having permissive attitude towards premarital sex. Participants who have and adequate knowledge on sexual health (p<.001), smoke or vape (p=0.05) and consume alcohol (p<0.001) were more likely to have permissive attitude towards premarital sex. Conclusion: Childhood abuse, especially emotional abuse, should not be underestimated. Permissiveness regarding premarital sex is of great concern. Permissiveness can lead to risky sexual behaviour. Preventive measures should be taken to promote positive attitudes toward premarital sex and to raise awareness about childhood abuse.