This research highlight the business activities and the role of small and mediumsized enterprises SME's in the national economy, and expectancy role of this sector is increasing economic activity, securing jobs and increasing gross domestic product GDP in general. It also focuses on the most important characteristics and features of the sector of SME's in Syria. In addition to review of the main weaknesses facing the national economy in general and this sector, in particular, which contributed to the derivation of many suggestions contribute to the advancement and development of business environment and SME's and to the promotion and support its role in national economy.