In this study, a new method based on Overall Equipment Effectiveness (OEE) is presented to improve equipment effectiveness of a Small and Medium Sized Enterprise (SME). As known, the aim of OEE is to enable an increase in the productivity of equipment by revealing the equipment losses in the system. However, there are various difficulties that SMEs face when utilizing this tool. One of these difficulties faced by SMEs is to allocate time and money to these improvement studies. Another difficulty that arises during these studies is that application of OEE differs by the industry and production environment. In this study, a new method based on OEE is proposed by considering the above-mentioned difficulties. The proposed method is trying to find an answer to the question of "Which equipment should be improved to what extend?" during the improvement studies of SMEs (having limited resources). By applying of the method to a wood processing facility, an increase of the OEE value of the selected machine from %64.7 to %72.4 is observed and this in turn positively affected the effectiveness of the selected production line.