When the 3D printed materials are used as substrate for thin overlays or liquid surface coatings, their surface roughness and wettability play an important role in determining the quality of the final product. In this study, effect printing layer thickness on surface roughness and wettability of 3D printed samples made from wood flour/PLA filament having 1.75 mm was investigated. For this aim, four different printing layers, 0.05 mm, 0.1 mm, 0.2 mm, and 0.3 mm, were used in the production of the 3D-printed specimens. Average roughness (R-z), mean peak-to-valley height (R-y) and maximum peak-to-valley height (R-y) were considered to evaluate the surface characteristics of the specimens. The surface properties of the specimens were determined by using a stylus profilometer (Mitutoyo SJ-301). The wetting behavior of the specimens was characterized by the contact angle method (goniometer technique). The surface smoothness of the specimens significantly improved with decreasing printing layers. The wettability of the specimens significantly increased with increasing printing layer thickness.