The lipolytic activity of Campylobacter pylori capable of gastric mucosal lipid degradation was investigated. The colonies of bacteria, cultured from antral mucosal biopsy specimens of patients undergoing endoscopy, were washed with saline and passed through a sterilization filter; the filtrate was examined for lipase and phospholipase A activities, using glycerol trioleate and dipalmitoyl phosphatidylcholine as substrates. The obtained results revealed that both enzymes are present in the C. pylori filtrate. The enzymes exhibited optimal activity at 37 °C and the pH range of 7.0–7.4. The major product of the triglyceride degradation was glycerol monoleate, while lysophosphatidylcholine resulted from the degradation of phosphatidylcholine. The lipase activity of the C pylori filtrate was inhibited by an antiulcer drug, sofalcone, which at a concentration of 200 µg/ml caused a 43 % reduction in the triglyceride hydrolysis. The sofalcone, however, showed only marginal, if any, inhibitory activity toward C pylori phospholipase A. The results suggest that C pylori infection may be detrimental to the integrity of gastric mucosal lip