The title compound, [Li(C12H21NSi)(C6H16N2)], is an intermediate in the synthesis of the corresponding organometallic compounds. The molecule has an unusual C-Si-N-Li four-membered heterocycle which adopts a folded conformation, with the coordination around the Li, N, C and Si atoms being distorted tetrahedral. Its structure is strongly supported by 1H NMR, 13C NMR and 13C-1H correlation spectra. The compound has potential for application in the synthesis of other novel organometallic compounds.