A preparation of thrombolytic enzymes of micromycete S. strictum 203 was obtained and characterized. The expressed urokinase activity of producer proteinases was determined, and the content of the complex of three alkaline trypsin-like thiol-dependent serine-type proteinases with different isoelectric points (4.5, 7.2 and 11.8) but close molecular weight was detected in the enzyme preparation (about 35 kDa). One of the proteinases (proteinase III) was not glycosylated, and the rest were glycoproteins. The proteinases differed in the spectrum of proteolytic activity in relation to proteins; the thrombus components also turned out to be different. Presumably, the enzymatic urokinase activity causes proteinases to activate plasminogen.