Hydrocyclones used for solid-liquid separation are usually composed of a single inlet. In this paper, we designed hydrocyclone with a new type of tangentially corner inlet structure for separation and compared with the tangentially corner inlet and the conventional tangent inlet structure hydro-cyclones, studied the characteristic of their tangential velocity, radial and axial velocity distribution. Simulation results showed that the RSM turbulence model and SIMPLCE algorithm can be used in analyzing the velocity field and the tangential velocity is increased more than 16.9% in the tangentially corner inlet hydrocyclone, and also, the separation efficiency is enhanced. The designer can use these results for optimizing the structure of hydrocyclone in the future.