The impact of Struve's astronomical dynasty on the development of astronomy in Ukraine in XIX—XX centuries is studied. First of all, the role of V. Ya. Struve and O. V. Struve in the formation of astronomical research programs at the Kharkiv, Kyiv, Odesa, and Mykolayiv observatories, in equipping observatories with instruments, in practical trainings of astronomers as well as in the organization of astronomy-geodetic expeditions (XIX cent.) is analysed. Particular attention is paid to the activity of L. O. Struve as the director of the Kharkiv observatory. We give a brief analysis of the O. L. Struve’s works conducted together with G. A. Shajn and B. P. Gerasimovich (XX cent.) as well as of the effect of his scientific and public activity on the development of astronomy in the former Soviet Union and in Ukraine. Some important documents from the archives of the RAS and om state archives of Ukraine are cited.