► This study was conducted to determine the effect of the thermal modification process in hot-press on the wettability and surface roughness characteristics of the eucalyptus wood board. ► The roughness measurements, average roughness ( R a), and maximum roughness ( R max) were performed based on both parallel and perpendicular to the grain using a fine stylus tracing technique. ► Contact angle measurements were obtained by using a goniometer system connected with a digital camera and computer system The results showed that surface roughness values of the modified wood boards using hot-press significantly decreased with increasing press pressure and with decreasing temperature. ► The contact angle measurements indicated that the thermal modification had a significant influence on the siarface wettability of the wood boards Statistical analyses showed significant differences an the surface roughness and contact angle values of the wood boards following thermal modification. ► The results acquired in the present work provide important information for future research and utilization of the thermally modified wood boards. The aim of this study was to investigate the effect of the thermal modification process by hot-press on the wettability and surface roughness characteristics of the eucalyptus wood boards. The roughness measurements, average roughness ( R a), and maximum roughness ( R max) were taken both parallel and perpendicular to the grain using a fine stylus tracing technique. Contact angle measurements were obtained using a goniometer system connected to a digital camera and computer system. The results showed that surface roughness values of the modified wood boards using a hot-press significantly decreased with increasing press pressure and with decreasing temperature. The contact angle measurements indicated that the thermal modification had a significant influence on the surface wettability of the wood boards. Statistical analyses showed significant differences in the surface roughness and contact angle values of the wood boards following thermal modification. The results acquired in this work provide important information for future research and utilization of the thermally modified wood boards.