Mental disorders such as anxiety, depression, and stress-related conditions are increasing globally, driven by lifestyle disturbances, emotional dysregulation, and social stressors. Ayurveda offers a holistic preventive lens through Sadavritta (Good Conduct), a comprehensive code of ethical, behavioural, and lifestyle conduct aimed at promoting mental discipline and psychological well-being. This conceptual study explores the preventive role of Sadavritta in mental disorders by reviewing classical Ayurvedic texts (Charaka Samhita, Sushruta Samhita, Ashtanga Hridaya) and contemporary scientific evidence. Key Sadavritta principles identified include lifestyle regulation, emotional hygiene, ethical social conduct, mindfulness, and self-discipline. These principles support mental health by enhancing Sattva (clarity and stability), regulating circadian rhythms, strengthening emotional resilience, reducing stress responses, and improving social harmony.  Modern research parallels these concepts, demonstrating that mindfulness, lifestyle regulation, social connectedness, and emotional regulation significantly reduce the incidence of mental disorders. The findings suggest that Sadavritta functions as a multidimensional preventive tool that aligns with modern preventive psychiatry and lifestyle medicine. Integrating Sadavritta into contemporary mental health strategies may provide an effective, culturally rooted, and low-cost approach to reducing the burden of mental disorders. Further clinical validation is recommended.