Axial-flow hydrocyclone is a new type of hydrocyclone which is proposed on the basis of tangential hydrocyclone. Its key part is rotating and accelerating component - the guided vane. The structural particularity made it necessary to pay attention to the internal flow field of axial-flow hydrocyclone. In view of the progress of CFD technique and mature of calculation condition, numerical simulations were carried on single-phase flow in axial-flow hydrocyclone by using Fluent software and Reynolds Stress Model. The initial conditions were that fluid medium was water and the overflow rate was 15%. The pressure and velocities fields were analyzed in the whole hydrocyclone and the specific effects of guided vane were studied. At the same time, through the verification of LDV experiment, the simulated values of water phase matched well with the experimental values. Crown Copyright (C) 2010 Published by Elsevier B.V. on behalf of The Institution of Chemical Engineers. All rights reserved.