The purpose of this paper is to systematically analyze the knowledge management research within small and medium-sized companies. The study includes a systematic review of 30 peer reviewed papers on knowledge management advantages for SMEs. Balanced scorecard perspectives cover all aspects of the organization, and, consequently, the balanced scorecard approach has been applied to classify the KM benefits. The reviewed scientific studies highlight the benefits of knowledge management in the areas of economic and social perspective (increased profits, flexibility, product reputation, financial performance), commercial and customers perspective (market share, sales growth, customer satisfaction, good external relationship), internal business processes perspective (operational performance, increased productivity, product/service quality, process improvement) and organizational learning and growth perspective (employee development, innovation, organizational creativity, learning).For future studies, determining stakeholder views is recommended in order to gain sustainable competitive advantage.