Spirulina is a marine blue green algae which is being extensively studied as the biomass of these microalgae and the compounds they produce have been shown to possess several biological applications with numerous health benefits. Apart from being used as nutraceutical food supplement worldwide, it shows therapeutic benefits on an array of diseased conditions including hypercholesterolemia, hyperglycerolemia, cardiovascular diseases, inflammatory diseases, cancer and viral infections. Spirulina is also incorporated as a functional ingredient in food products and beverages. The people in Africa have been known for consuming as Arthrospira (formerly, Spirulina) as principle food for past 100 years. But it became famous after it was successfully used by NASA as a dietary supplement for astronauts on space missions. There have been numerous studies investigating the efficiency and current clinical applications of Spirulina in treating several diseases in the recent years.