The work is devoted to the analysis of scientific life of one of the leading orientalists of the first half of the 20th century I. I. Umniakov, who continued traditions of Russian pre-revolutionary orientalism. The main directions of his scientific creativity are highlighted: research of the Tokhar history, research and preservation of monuments of ancient and medieval culture, research of international relations of Central Asia in the era of Amir Timur. The main works of I. I. Umniakov on each of the directions are analyzed, in particular the possibility of comparing Tokhar and Kushaṇa, which is one of the key problems for the history of ethnogenesis and polytogenesis of Central Asia in antiquity. The conclusions obtained by Umniakov are compared with the modern level of research on the selected problems, their high relevance for modern science is highlighted. The important side of I. I. Umniakov’s activity was the popularization of science. In this context, a previously unknown document is published: a letter from I. I. Umniakov to M. E. Masson dated April 3, 1957, in which the author speaks about the unenviable fate of the book “Samarkand”, which was published only in 1957.