Plant-based drug discovery represents a critical intersection between traditional ethnomedicine and contemporary pharmaceutical development, offering a rich repository of structurally diverse bioactive compounds with validated therapeutic potential. This review examines the translational continuum from ethnobotanical knowledge to clinically approved therapeutics, emphasizing pharmacologically relevant strategies that have successfully bridged indigenous healing practices with evidence-based medicine. Ethnomedicine-guided bioprospecting has yielded numerous lead compounds targeting complex diseases, including cancer, infectious diseases, cardiovascular disorders, and neurodegenerative conditions. The phytochemical diversity inherent in medicinal plants provides scaffolds for novel drug candidates, with alkaloids, terpenoids, polyphenols, and glycosides demonstrating specific molecular interactions with validated therapeutic targets. Modern drug development approaches integrate advanced screening platforms, omics technologies, and computational modeling to accelerate the identification and optimization of plant-derived bioactives. Despite significant successes, translational barriers persist, including standardization challenges, bioavailability limitations, and regulatory complexities that impede the progression from preclinical validation to clinical implementation. This review synthesizes current knowledge on plant-based drug discovery pipelines, mechanistic pharmacology of key phytochemicals, and strategies for overcoming translational obstacles. By examining both established plant-derived therapeutics and emerging candidates in clinical development, we provide a comprehensive framework for leveraging botanical resources in modern drug discovery. Future directions emphasize the integration of artificial intelligence, systems pharmacology, and precision medicine approaches to unlock the full therapeutic potential of the plant kingdom.