The surface roughness of pine, beech, and oak wood cut in the abrasive water jet (AWJ) system was evaluated for different processing parameters. Wood specimens were prepared in thicknesses of 18, 36, and 54 mm in both tangential and radial directions. Then the specimens were cut, applying three different feed speeds (50, 100, and 200 mm/min), three different abrasive flow rates (200, 300, and 450 g/min), and two different cutting liquid pressures (300 and 380 MPa) with the AWJ system. The Ra and Rz roughness values were higher in the tangential cut for pine and oak specimens and in the radial cut for beech wood. Roughness values increased in all specimens with increases in the AWJ feed speed and the wood thickness. In contrast, with increased amounts of abrasive, Ra and Rz values of the specimens decreased and surface smoothness tended to increase. Roughness values of pine and oak specimens generally decreased due to the increase in liquid pressure. However, an increase in the roughness of the beech specimens was determined. As a result, the feed speed and wood thickness were the most influential parameters on the roughness of specimens. In contrast, the cutting direction and liquid pressure showed less importance on the roughness.