In this paper we want to examine how enterprise resource planning (ERP) systems effects on small and medium-sized enterprises (SMEs) Kavala's region. We consider several SMEs of our region, we use data from each SME and we form a questionnaire to secure more data from the enterprises. We weight up the factors that affect the choice of ERP. Also, we relate these factors with basic characteristics of the specific SMEs of our region. Flexibility and functionality are the most important criteria of choosing an ERP system. Surprisingly, the cost is one of the less important criteria. Also, minor effects have criteria such as brand, name and position of the vendor. Finally, we indicate issues for future research.