The present invention relates to crosslinked polyurethane-polyurea powders which are prepared by a process which comprises dispersing NCO semiprepolymers in an aqueous medium, forming powders and isolating the powders from the aqueous medium, the NCO semiprepolymers having an NCO content of 10 to 20%, being liquid at room temperature and/or dissolved in isocyanate-inert, water-soluble solvents and based on the reaction product of(a) a polyisocyanate component based on at least one organic polyisocyanate with a polyol component having an average hydroxyl functionality of 2.3 to 4.0 and containing(b) a hydrophobic polyol component containing less than 25% by weight of ethylene oxide units, --CH.sub.2 --CH.sub.2 --O--, and(c) a hydrophilic polyether component comprising monohydric or polyhydric alcohols containing at least 70% by weight of structural units corresponding to the formula ##STR1## The present invention also relates to a process for the preparation of these crosslinked polyurethane-polyurea powders and to their use as fillers in two-component polyurethane coating compositions.