Abstract: Loneliness has emerged as a significant public health concern affecting individuals across all age groups and socioeconomic backgrounds. Defined as the subjective feeling of inadequate social connection, loneliness differs from social isolation, which refers to the objective absence of social relationships. Increasing urbanization, population aging, technological changes, migration, and shifts in family structures have contributed to a growing prevalence of loneliness worldwide. Research has demonstrated that chronic loneliness is associated with adverse physical, psychological, and social outcomes, including cardiovascular diseases, depression, anxiety, cognitive decline, weakened immunity, reduced quality of life, and premature mortality. Consequently, international health organizations and governments have recognized loneliness as a critical public health challenge requiring coordinated interventions. Community nurses occupy a unique position in identifying, preventing, and addressing loneliness through health promotion, early detection, community engagement, psychosocial support, and intersectoral collaboration. This review explores loneliness as a public health crisis, examines its determinants and health consequences, and highlights evidence-based community nursing interventions designed to foster social connectedness and improve population health outcomes. The article emphasizes the essential role of community nurses in developing resilient communities where social inclusion, emotional support, and meaningful relationships contribute to overall well-being.