Although the particle adhesion is a classic problem in cyclones, it is not clearly understood in previous studies. This study was set out to determine factors affecting the micro-particle adhesion in an acrylonitrile butadiene styrene cyclone by developing a mesh-free simulation method to predict the dynamic motion of a single particle in a 2D horizontal section of the cyclone with the presence of the wall boundary layer. Simulation results showed that the centrifugal force played a minor role on the particle adhesion but it was important on the transportation of the particle. In contrast, the electrostatic force was important on the particle adhesion but it was not important on the transportation of the particle. Moreover, simulation results suggested that the particle adhesion can be reduced by increasing the inlet velocity of the cyclone or by increasing the coefficient of restitution of the particle-wall collision. In contrast, the particle adhesion can be increased by increasing the radius of the cyclone, the particle charge and the coefficient of friction. Furthermore, simulation results on the effect of the inlet velocity and particle charge were validated by experimental results.