Streptokinase (SK) is a specific effective medicine for thrombolytic therapy of acute myocardial infarction. This study established a process for the pilot production of recombinant streptokinase (r-SK). Engineering bacteria were fermented in a 20-1 fermentor to produce r-SK After simple renaturation and purification, 12.9 g of r-SK with 97.8% of purity and about 10(5) IU mg(-1) of specific activity was obtained, the yield of protein and the recovery of activity were 44.9% and 51%, respectively. Finally, the r-SK was made into about 700 doses of injections for clinical applications.