Spirulina (family oscillatoriaceae) is a multicelllular, filmentous cyanobacterium, belonging to a blue-green alga of cyanophta. Spirulina platensis is one of the oldest alga species on earth and has a history of about 3 billion years. It grows usually in alkaline waters of Africa, Asia, North and South America. It has been used for over a thousand years as a source of food because of its high protein content and good amino acid composition. This blue green algae used in daily diets in natives in Africa and America have found to be a good source of carotenoids, micronutrients, tocopherols and beta-carotene. Spirulina contains unusually high levels of gamma-linolenic acid, an essential polyunsaturated fatty acid. In particular, the blue-green microalgae spirulina platensis has been used for regulation of immune response, and it still occupies and important place in traditional Chinese medicine. It is also a source of vitamin A and Vitamin E.