Objectives: Mental health is vital for individuals to effectively cope with stress, perform academically, and contribute to society. This study aimed to examine the relationship between the mental health and spiritual intelligence of medical students. Materials and Methods: The study was conducted on 226 medical students from Shahid Beheshti University of Medical Sciences in 2022. Convenient sampling was used to select participants. Data collection involved the use of demographic, spiritual intelligence, and mental health questionnaires. Results: The mean age of the participants was 24.87 ± 2.24. Regression test results indicated that spiritual intelligence could predict somatic symptoms (p=0.021), anxiety and insomnia (p=0.012), social dysfunction (p=0.018), and severe depression (p=0.022). There is a significant relationship between marital status and mental health (p=0.031), as well as between gender and spiritual intelligence (p=0.048). However, there was no significant relation observed between marital status and spiritual intelligence (p=0.839), and between gender and mental health (p=0.560). Pearson’s correlation test demonstrated a direct and significant relationship between mental health and spiritual intelligence (R=0.211; p=0.012). Conclusion: The discussion of the findings emphasizes the importance of spiritual intelligence as a determining factor for the mental health of medical students. Recognizing the significance of mental health in this group, interventions that aim to enhance their spiritual intelligence should be considered. It is recommended that educational institutions and healthcare professionals implement interventions and programs that foster the spiritual intelligence of medical students.