Abstract: Mental health disorders constitute a significant global public health challenge, affecting individuals across all age groups and socioeconomic backgrounds. Despite increasing awareness regarding mental health issues, a substantial treatment gap continues to exist due to stigma, inadequate mental health literacy, shortage of mental health professionals, and limited access to mental health services. Mental Health First Aid (MHFA) has emerged as an evidence-based educational intervention designed to improve public understanding of mental health conditions and equip individuals with the knowledge and skills required to recognize, support, and guide persons experiencing mental health crises. Community Health Nurses (CHNs) play a crucial role in implementing MHFA training programs because of their accessibility, trusted position within communities, and expertise in health promotion and disease prevention. This review explores the concept, principles, components, effectiveness, and implementation of Mental Health First Aid training delivered by Community Health Nurses. It examines the role of CHNs in enhancing mental health literacy, reducing stigma, promoting early intervention, and strengthening community resilience. The review also discusses challenges associated with MHFA implementation and highlights future directions for integrating MHFA into community health nursing practice. Evidence indicates that MHFA training significantly improves participants’ confidence, knowledge, attitudes, and helping behaviors toward individuals experiencing mental health problems. The integration of MHFA training into community health programs can contribute substantially to early detection, timely referral, and improved mental health outcomes, thereby supporting the broader goals of public mental health promotion and community well-being.