Chestnut blight caused by Cryphonectria parasitica, is among the most important fungal diseases of European chestnut. However the aggressiveness of the pathogen to other tree species of the Fagaceae family (oaks, beech) is increasing in relevance. Blight symptoms were detected on the bark of oak species (Quercus spp.) in many countries since 1960. In Hungary first observation of symptoms of the disease was reported on sessile oak in 2002. Then the fungus was reported also on oaks in Slovakia and in Romania. The main goal of our study was to examine the susceptibility of oak species to C. parasitica. Virulence of different isolates was examined on dormant sticks of 9 different oak species and European chestnut as a control. Shoots were infected with virulent isolates of C. parasitica. The size of the caused ellipse shaped cankers on the inoculated branches was measured. Necroses on red oak were significantly larger in size than those on the chestnut. Q. rubra and C. sativa were more susceptible than the other species, and sessile oak (Q. petraea) and pedunculate oak (Q. robur) also showed a high susceptibility. Results demonstrate that most oak species are susceptible to C. parasitica (at various levels), red oak (Q. rubra) being the most susceptible to the chestnut blight fungus.