This book is divided into two parts. Part-I deals with Description of Medicinal Plants and Part-II with Hypericum perforatum L. It describes various medicinal plants used in Ayurveda. It provides indepth knowledge about the plants used in Indian System of Medicine. The plants have been discussed as per syllabus of Dravyaguna (Ayurevedic Pharmacology). Hypercium perforatum Linn., popularly known as St. John's wort, has recently received attention of the medical world. This plant has been desc-ribed in detail with Chemical Composition with various uses. The book will serve as useful guide for students and practitioners of Ayurveda