The study brought closer socio-economic determinants of the development of small and medium-sized enterprises on the example of the district of Plock. For this purpose, the results of own research, secondary data from the Central Statistical Office and report on the state of small and medium-sized in Poland in 2013-2014 prepared by PARP as well as literature were used. The study shows that almost every other entrepreneur running a business to invest their own savings, and only one in four use the bank credit. The vast majority of entrepreneurs intend to further develop the company’s business activities. As the main barrier to doing business was high fees prescribed by law, which is compulsory payments to social insurance, taxes and stamp duties. Therefore, to simplify the burdensome regulations on starting and running a business is an important challenge for policy.