Using anhydrous hydrazine and trimethyl chlorosilane as raw materials, 1, 2-bis(trimethylsilyl)hydrazine was synthesized with the yield of 83%. Then through activation of butyllithium, tris(trimethylsilyl)hydrazine were synthesized with the total yield of 75%. Further through solvothermal reaction of lithium-tris(trimethylsilyl)hydrazine and trimethyl chlorosilane, tetra(trimethylsilyl)hydrazine were synthesized with the total yield of 34%. Their structures were characterized by means of NMR, IR, MS and elemental analysis. The self-condensation reaction of mono(trimethylsilyl)hydrazine and rearrangement reaction of bis(trimethylsilyl)hydrazine induced by heat action were analyzed. Results show that these reactions are caused by the inter-and intra-molecular migration of trimethylsilyl group on hydrazine, and isomerization of bis(trimethylsilyl)hydrazine could occur obove 75 ℃.