Edge preparation is a process to modify edge geometry and surface integrity of cutting tools. Cutting tools life can be improved by edge preparation. Edge preparation experiments of tungsten carbide tool were carried out with nylon abrasive brushes on lathe machine. Cutting tool edge surface was observed with optical microscope. Orthogonal experiments and single experiments were finished. The experimental results showed that smooth round cutting edge was obtained. The brushing time and rotational speed are the main influence parameters of edge preparation efficiency, followed by abrasive nylon brush abrasive size and feed rate. The tool round edge radius is decreased with the increase of abrasive size number. The tool round edge radius is increased with the increase of feed rate and rotational speed.