The invention provides a ring-opening reaction process for epoxyalkane and use of n-heterocyclic carbine as a ring-opening reaction catalyst for epoxyalkane. The process comprises the step of carryingout ring-opening reaction on an initiator and epoxyalkane under the catalytic action of the catalyst, namely n-heterocyclic carbine. According to one embodiment of the invention, n-heterocyclic carbine is taken as the ring-opening reaction catalyst for epoxyalkane, so that the raw materials are cheap, the preparation is simple, the catalyst is environment-friendly and high in catalytic activity,and the post-treatment is easy.