Abstract: (Ti,W,Mo,Nb,Ta)(C,N) solid solution nano-powders were synthesized by high energy ball milling and carbothermal reduction-nitridation. The effects of reduction temperature and reduction time on the phase composition, lattice constant and content of C and N of the powders were analyzed using X-ray diffractometer, scanning electron microscope and elemental analyzer. The results show that the solid solution degree of metal elements in Ti(C,N) was in the order of Ta, Nb, W and Mo. With the increase of reduction temperature or extension of reduction time, the lattice constant, C content and particle size of the solid solution powders increased gradually. After carbothermal reduction-nitridation at 1 500℃ for 1 h, the (Ti,W,Mo,Nb,Ta)(C,N) solid solution powder with a single phase and average particle size of 100 nm was obtained, which contained 9.1wt% C and 7.2wt% N.