Introduction: Khat chewing has been a common habit throughout the Horn of Africa and the Arabian Peninsula for thousands of years. It is estimated that more than 20 million people in Africa and the Arabian Peninsula are adolescents. This study aimed to assess the knowledge, attitude, and self-efficacy of khat chewing among adolescents in Mogadishu, Somalia. Method: A cross-sectional study with a sample of 284 adolescents was used. A self-administered pretested questionnaire was used after obtaining an ethical approval from Universiti Putr Malaysia. Data were coded, entered, and statistically analyzed. Results: The prevalence of khat chewing among respondents was 10.2%. Almost more than half of the participants had poor knowledge (184, 64.8%) and self-efficacy (154, 54.2%), while 140 (49.3%) respondents had positive attitudes. Significant predictors of the students’ knowledge of khat chewing included monthly income of more than 500$ (AOR: 2.145), family history such as cousin (AOR=0.347), fathers with a high school (AOR=1.75) and a college degree (AOR=2.21). Significant predictors of the students’ attitude towards khat chewing included family income of 100-299 USD (AOR=0.5), fathers’ with a high school (AOR=2.5) and college (AOR=2.4). Significant predictors of the students’ self-efficacy to resist khat chewing included family income of 100- 300$ (AOR=2.25), fathers with a high school (AOR=2.6), and khat accessibility that is fairly difficult (AOR=0.63) and fairly easy (AOR=0.55). Conclusion: The study highlights the need for increased awareness and education about the adverse effects of khat chewing and the importance of addressing social norms and peer pressure in shaping adolescent attitudes toward Khat.