The escalating demand for sustainable and cost-effective feed solutions in aquaculture has catalyzed interest in indigenous plant-based additives as viable alternatives to synthetic compounds and conventional fishmeal-based formulations. This review critically assesses the biological efficacy, functional roles, and practical application of indigenous botanicals in aquaculture nutrition, emphasizing their potential to enhance growth performance, feed utilization, and health outcomes in aquatic species. Key plant species such as Moringa oleifera, Azadirachta indica, Curcuma longa, and Ocimum sanctum have demonstrated promising immunostimulatory, antioxidant, antimicrobial, and digestive-enhancing properties. The review highlights the importance of species selection, harvesting timing, and post-harvest processing techniques in preserving phytochemical integrity and reducing antinutritional factors such as tannins, phytates, and saponins. Case studies reveal substantial improvements in specific growth rate (SGR), feed conversion ratio (FCR), enzyme activity, and disease resistance when these additives are incorporated in fish diets at optimal levels. However, the presence of anti-nutritional compounds and variability in phytochemical content across regions necessitate rigorous standardization and detoxification strategies to ensure safety and consistency. Integrating traditional ethnobotanical knowledge with contemporary aquafeed science emerges as a strategic pathway to support environmentally sustainable, economically viable, and nutritionally robust aquaculture systems. The review concludes by advocating for continued interdisciplinary research, policy support, and community engagement to harness the full potential of indigenous plant resources for global aquaculture sustainability.