AbstractA conceptual design study of the DEMO reactor is being carried out in Russia. The main efforts are concentrated on the study of steady state reactor DEMO-S. This reactor will be operated with an advanced plasma regime involving a high fraction of bootstrap current. A divertor concept with open liquid lithium as a plasma facing material was chosen. Two extreme approaches were analyzed: the first assumes that liquid lithium is loaded with direct heat flux from 100 to 150 MW m−2; the consumption of liquid lithium and a form of lithium surface are defined; in the second approach lithium plasma dynamics in the divertor is analysed using the 2-D MHD divertor code. With this approach heat loads are considerably decreased by the radiation. Some additional issues connected with utilization of vanadium alloys in the DEMO reactor, including environmental and safety aspects, material activation and refabrication were also analyzed.