[1,3]-Sigmatropic rearrangement of 2-vinylsilirane (2-vinylsilacyclopropane) to silacyclopent-3-ene has been studied for the first time with quantum chemical methods. The PBE/TZ2P and B3LYP/6-31G(d) levels of theory have been used to explore the potential energy surface of the title reaction. The energies of the stationary points have also been evaluated with the G3(MP2)//B3LYP method. Several transition states corresponding to suprafacial and antarafacial pathways of the rearrangement have been found. The lowest energy pathway is a symmetry-allowed suprafacial sigmatropic shift with G3(MP2)//B3LYP activation energy of 97kJ/mol.