Science in the Mathnawi of Maulawi presents the contemporary scientific thought and knowledge depicted in the Mathnawi of Maulawi. The Mathnawi of Maulana Jalaladdin Maulawi (1207-1273) is one of the greatest impressions throughout the history of the Persian literature. Maulana Jalaladdin Maulawi, most usually known as Rumi, has, in the 13th Century, introduced by composing the six books of Mathnawi, numerous distinguished intellectual, philosophical, psychological and scientific thoughts; many of his doctrines, today, appear in the areas of physics, cybernetics and system theory. Though most of his ideas were not realized, but were denied, in the medieval ages; they are well established contemporary scientific facts and knowledge, today, after centuries. There are complete translations of Mathnawi in English, Turkish, Hindustani, and German. Some of these contain only extracts of parts of the six books of Mathnawi. Judged by modern standards, the Mathnawi is a very long poem: it contains almost as many verses as the Iliad and Odyssey together and about twice as many as Divine Commedia; and these comparisons make it appear even shorter than it actually is. Mathnawi, in its six books, contains 25700 verses. However, the mathnawi, it has been said, "is easier than easy to the ignorant, but harder than hard to the wise". Interpretation of Mathnawi is the most important task that has yet to be accomplished, in order to reveal the breadth and depth of Maulawi's genius most adequately. Hence, it seems evident that presenting, highlighting and interpreting Maulawi's scientific thoughts and doctrines, is of major significance in the history of sciences. The book attempts to undertake the task and hope to pave the way for other researchers and authors to follow the path in their own expertise.