In this study, barriers to internationalization for wood processing and wood trading firms in Slovakia are identified. Specifically, the perceptions of 62 Slovak firms were examined regarding entry into European Union markets. In addition to competitive issues, the influence of previous experience with international business and firm size on perceptions of barriers to enter foreign markets was examined. Results suggest that foreign competition is considered to be the most significant barrier due to a low level of innovation from domestic companies. In addition, the need to invest in promotional activities and limited access to capital are also significant barriers to entry into EU markets. Firm size was not found to be correlated with market barriers and no significant differences in perception of barriers was found between firm owners and managers.