PURPOSE: To investigate the biocompatibility and biodegradability of a membrane made from porcine peritoneum. METHODS: The membrane (5x5 mm) was inserted in the subcutaneous tissue on the back of 15 mice, which were killed after 1, 3 and 9 weeks (ISO 10993-6). The cellular components of the inflammatory response and degradation of the membrane were analyzed in hematoxylin-eosin-stained histological sections. RESULTS: After one week, mononuclear cells were observed inside the membrane. After three weeks, the material was almost completely absorbed. After nine weeks, there was no presence of material and there were signs of tissue remodeling. There was neither a foreign body reaction nor signs of tissue necrosis. CONCLUSION: The collagen membrane derived from porcine peritoneum is biocompatible and bioabsorbable when implanted in the subcutaneous tissue of mice.