Reactions of hydrosilanes, R4-nSiHn (R = alkyl or phenyl, n = 1-3), with 2 equiv of CuBr2 in the presence of a catalytic amount of CuI led to selective replacement of an H-Si bond with a Br-Si bond giving R3SiBr, R2SiHBr, or RSiH2Br, while treatment of R2SiH2 and RSiH3 with 4 equiv of the reagent produced R2SiBr2 and RSiHBr2, respectively. Similar reaction of HEt2SiSiEt2H afforded HEt2SiSiEt2Br.