The investigation was conducted in 47 patients, operated on for pancreatic pseudocysts (PP). Activity of matrix metalloproteinases (MMP-9) and content of their tissue inhibitor (TIMP-2) were determined in the blood serum for estimation of inflammatory factors, hypoxia severity and state of the pancreatic tissue reconstruction. High activity of MMP-9 and TIMP-2 in presence of PP types I and II was noted in patients, what, probably, is caused by compensation reaction, directed towards inhibition of the collagen system destruction (predominantly of collagen type IV) and prevention of further reconstruction of pancreatic connective tissue. While progressing of pancreatic fibrosis the MMP-9 activity and the TIMP-2 level have lowered in comparison with these indices while its absence. In PP type III the MMP-9 activity was by 83.6% higher, than in a control group, but, by 51.4 and 35.1% lower, than in PP types I and IV. In all the patients endothelial dysfunction with endothelial injury was observed, witnessed by significant rising of the VEGF content in the blood serum. It have created favorable conditions for pancreatic tissue remodeling while parenchymal defect have been constituted by tissue, owing lower level of organization, including a cicatricial one. In cases of cellular repeated affection more activation of pancreatic stellate cells and enhancement of production of extracellular matrix component were noted.