Abstract: Medicinal plants are those plants which are used for medicinal purposes. Medicinal plants are come under herbalism (herbal medicine). From the ancient time herbal plants were used for medicinal purposes. India was rich in medicinal plants from prehistoric time. Different parts of plants are used for medicinal purposes. It has been observed that the contribution of USA in medicinal plants is just 25% whereas India contributes 80% of its share. Medicinal plants are used to treat skin problems, eye irritation, diarrhea, sleeplessness and nausea. The medicinal plants like tulsi, ginger, turmeric and aloe are used for curing several common ailments. Nitrogen is one of the essential plant nutrients. It plays an important role in the life cycle of plant. Nitrogen is the main constituent of amino acids, proteins and chlorophyll. Nitrogen increases the vegetative growth of plants. It also increases the oil content present in the medicinal plants.