Background: The academic performance of medical students may affect their competence in future career prospects. Developing students' subjective well-being to improve academic performance is complex and has been investigated for many years. This cross-sectional study assessed the relationship between academic performance, general intelligence, and medical students' positive well-being.Methods: This cross-sectional, internet-based survey included male and female medical students from preclinical and clinical years at one of the largest public-sector universities in Riyadh, Saudi Arabia, between February 2020 and April 2020. The questionnaire included the World Health Organization-Five (WHO-5) Well-being Index, the Draw-A-Person Intellectual Ability (DAP: IQ) Test, and the Academic Success Inventory for College Students (ASICS). Academic performance was represented by a self-reported highgrade point average (GPA). Logistic regression was used to assess the association between academic performance and each of the well-being scores, intelligence, and academic success factors. Statistical significance was established at a p-value less than 0.05.Results: Responses were received from 176 medical students. Most participants were males (93.8%). There was a significant association between GPA above 4.5 and the total WHO-5 well-being score (p = 0.013), the ASICS general skills (p = 0.007), perceiving instructor efficacy (p = 0.005), confidence (p < 0.001), personal adjustment (p = 0.023), and lack of anxiety (p = 0.006). No association was found between GPA and intelligence quotient (IQ) or well-being when other factors were adjusted.Conclusions: Good academic performance is associated with subjective well-being and domains of academic success, such as perceived efficacy of the instructor, confidence, and personal adjustment. Implementing student development programs in medical schools can have a positive impact on students' academic performance and skills. Future studies assessing the different student support and development programs and their impact on academic success are needed.