1,2-Dilithiotetrakis(trialkylsilyl)disilanes [(R3Si)2SiLi]2 (R3Si = t-BuMe2Si and i-Pr2MeSi) were prepared as stable off-white powder by the reduction of the corresponding tetrakis(trialkylsilyl)disilenes with lithium in THF. The 1,2-dilithiodisilanes reacted with water, iodomethane, and chlorosilanes to give the corresponding disubstituted products in high yields.