Invasive alien plant species have emerged as a critical environmental and socio-economic concern in India, posing serious threats to biodiversity, agricultural productivity, and rural livelihoods. Among these, Neltumajuliflora (formerly Prosopis juliflora) has exhibited rapid and uncontrolled spread across arid and semi-arid regions since its introduction during the colonial and post-independence periods for afforestation, fuelwood supply, and wasteland development. Its ecological dominance has led to suppression of native vegetation, degradation of agricultural lands, reduction of grazing areas, and alterations in soil properties, thereby intensifying land and water resource pressures. This study focuses on the historical introduction, ecological impacts, and socio-economic consequences of N. juliflora invasion, with a special reference to Tamil Nadu, one of the most severely affected states. Employing a descriptive and analytical research design, the study utilises secondary data from government reports, published research articles, policy documents, and forest department records, supplemented by qualitative field observations and interactions with local farmers, pastoralists, and forest officials. The analysis includes district- and state-level estimates of species coverage and economic losses, as well as statistical evaluation of the financial burden imposed by invasive species per hectare. Findings reveal that N. juliflora dominates large areas of Tamil Nadu and other Indian states, causing the highest economic loss among major invasive plants due to groundwater depletion, farmland monopolisation, and disruption of rural livelihoods. The study emphasises the necessity of targeted, species-specific management strategies, early detection and rapid response mechanisms, and integration of community-based ecological restoration with policy and livelihood interventions. The results provide valuable insights for policymakers, environmental planners, and local governance institutions aiming to mitigate the ecological and economic impacts of invasive plant species in India.