The article studies the analysis done by American scholar Y.Bregel (1925-2016) of the poet, historian, translator and statesmen Munis and Ognahiy’s “Firdavs ul-Iqbal”. “Firdavs ul- Iqbal” is a unique encyclopedic work that reflects the history, culture, ethnography, literary environment and social processes of Khorezm in historical and artistic form. A comprehensive study of “Firdavs ul- Iqbal” interests not only local scientists but also foreign scholars, as a result, there is known and unknown studies appeared in scientific sphere. The study of the problem by foreign scholars has not been sufficiently researched. This scientific need served as the basis for covering one of the urgent problems of philology. Yuri Bregel was an American historian, orientalist, and author of several monographs on the history, culture and literature of Central Asia. In particular, the scientist studied the work “Firdavs ul-Iqbal” seriously, and dedicated to the history of the Khiva khans, and created a scientific critical text. He also translated the work into English and played an important role in acquainting foreign readers and scholars with the essence of the work “Firdavs ul-Iqbal” by Oghahiy and Munis. The preface by J. Bregel about the source consists of four parts. The first part is devoted to the works of Munis and Oghahi, the second part covers the properties of “Firdavs ul-Iqbal”, the third to the study of the work and the fourth part reveals the characteristics of handwritten copies of the source.The author of the article revealed the scientist’s research skill as much as possible based on Y.Bregel’s scientifically rich English preface.