The paper presents the results of experimental investigation of supercritical two-phase flow in steam-water injector. In the region of condensation shock wave, flow structures were captured with highspeed video camera simultaneously with recordings of pressure and temperature distributions. Visualisation of condensation terminus showed formation and evolution of vapour clouds. Their disappearance was accompanied by pressure pulses, which were recorded on the channel wall. In addition, dynamics of flow instability caused by excessive backpressure at the injector outlet was examined. (C) 2015 Elsevier Ltd. All rights reserved.