ABSTRACT The pre-treatment of wood surfaces using a radio-frequency (RF) discharge is attractive for various wood applications, mainly because of the high efficiency and low production cost of the process. The main advantage of this technique is that the bulk properties of the material remain unchanged while the surface properties are enhanced. Samples of wood pellets were exposed to a late afterglow RF plasma flow at atmospheric pressure. Experiments have shown that the argon plasma flow contains a number of long-lived active particles that can destroy the cellulose shell of the granules. Scanning electron microscopy was used to analyze the morphological changes on the surface of the wood granules resulting from interaction with plasma. The optimal range of operating parameters is discussed, as well as the main active components involved in the processing process.