The aim of the article is to determine the current state and future tasks of collecting, analysing and promoting the epic cycle "Forty Heroes of Crimea". The reviews in the article show, through about forty closely related epic compositions, that this cycle is a spiritual heritage in the world, providing insights into the history and world perception of the Nogayly era, considered the golden age of history for a significant part of Turkic peoples. The article analyses the works of native scholars, academicians, V.M. Zhirmunsky, E.M. Meletinsky, famous foreign scholars, N.K. Chadwick, K. Reichl, and other scholars. And these works should be a proof of the fact that Muryn Zhyrau was a gift to us of a cultural treasure of inestimable value. The article also highlights a great role of the M.O.Auezov Institute of Literature and Art. From the 1940s to the present day, the staff of the Institute has carried out a number of analyses of manuscripts and texts, which have greatly contributed to the implementation of the task of revealing the characteristics of written manuscripts and making them available to the public. The data presented in the article demonstrate all the serious consequences of not collecting the values in question in a timely manner and of not having all the recorded heritage available in archives. It is clear that the Kazakh people and the world have not had the opportunity to see this masterpiece as it deserves, if we look at the history of the promotion of these works in Kazakhstan and the world. On the basis of this, the article presents some views on how to solve this problem.