Phenomenon of the megaprojects as an instrument for the development of territories has not been studied thoroughly by the national economic science. There is lack of integrated, comparative analysis of the creation and the realization of territorial megaprojects in Russia and other countries. Authors of the article have set the goal to fill in this gap. A large scale investment project can obtain the status of the megaproject if it is characterized by a complicated character, high costs, systematic character and relevance of the realized targets. In the modern Russia the reconstruction of the historic territorial megaprojects and the realization of new ones as a relevant tool of the strategic territorial management is becoming the manifestation of contemporary institutional, organizational and informational transformations of the economic space of the global economic system. In contrast to financial investments, megaprojects are oriented on a real material result, having a considerable prolonged impact on the economic space. The authors regard infrastructural megaprojects construction of Transsib and BAM. The reasons of their achievements and failures are studies. The sustainable development of the regions of the Far East and Zabaikalye, the solution of important federal and regional tasks in the use of the resource, industrial and transit potential of the East of the country is connected mainly with the realization of the integrated infrastructural project of BAM’s and Transsib’s reconstruction. The article reveals the plans of the Government of the Russian Federation concerning the modernization of these megaprojects that will increase the capacity of BAM and Transsib by the year 2020 up to 75 million tons a year. The life cycle of the modern megaproject "Ural Industiral – Ural Polar" is revealed. The project was directed at the formation of a new economic skeleton in the Ural Federal District and creation of the prerequisites for the development of its problematic regions. Authors come to conclusion that this megaproject actually failed. It downgraded from a strategically important one into a conglomerate of local investment projects that are not interconnected by a single basic conception. Inevitably, this undermined its complex integration effect. The Olympic project “Sochi 2014” highlights the problem of post-project utilization of objects of territorial megaprojects. Only a few of them can immediately serve as drivers of regional economic complex. Others mostly generate losses. A set of policies and special measures of the regional authorities is needed to turn them profitable. The article also touches upon the American experience of megaprojects of the territorial development (Tennessee Valley Authority, Appalachian Regional Commission). Authors insist that analysis of the American experience can help the modernization of the strategic territorial management in Russia.