The features of the transformation of structural-phase states of a non-equiatomic multicomponent system based on refractory metals W-Ta-Mo-Nb-Zr-Cr-Ti after high-energy ball-milling of various durations are studied. Three main stages have been identified that differ in the morphology of the powder mixture, the distribution of components, phase compositions and the character of the change in microhardness. It was shown that already at the initial stage of treatment, two phases are formed, one of which (BCC-1) is a solid solution based on BCC (body-centered cubic) refractory metals, and the other (BCC-2) is a solid solution enriched in Zr, Cr and Ti. It has been suggested that the BCC-2 phase is a precursor state for the Laves phases that form during subsequent SPS (spark plasma sintering). A change in morphology and structural-phase composition is accompanied by a microhardness increase from 4.03 +/- 1.12 GPa after 1 min to 8.93 +/- 1.74 GPa after 15.5 min of treatment. (C) 2020 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.