The invention relates to a device for separating cut tobaccos, belonging to the technical field of the device for producing and processing tobaccos. The device provided by the invention comprises a separating mechanism of the mixture of cut tobaccos and dust, wherein the separating mechanism comprises a first-grade separating mechanism and a second-grade separating mechanism; the first-grade separating mechanism and the second-grade separating mechanism are connected through a hose. Compared with the prior art, the device provided by the invention has the advantages of novel structure and rational design; the device is more optimized compared with the traditional structure, the consumed material is reduced, the use is more convenient, the operation efficiency is greatly improved and the separating effect is obvious; the device can realize the effective separation of the cut tobaccos and the dust while guaranteeing that a dust-removing system is normally operated; the discharging of the wastes is reduced and the residual cut tobaccos in the smoke dust are completely recycled so as to avoid wasting cut tobaccos, so that the economic cost is correspondingly reduced and the economic benefit is improved; the device is suitable for being installed in the dust-removing system for producing and processing each type of tobacco and is suitable for being popularized and applied to similar gas-solid separation processes.