Abstract: Disclosed are a medical material and a production process thereof. The medical material has a membrane configuration and is produced by impregnating a membranous material with collagen or gelatin and then physically or chemically cross-linking protein molecules of the membranous material. The membranous material is essentially acellular compact layer of a biogenic connective tissue. The medical material may further be processed into other forms such as threads, braids, tubes and hoses and is useful in surgery. The medical material has a strength sufficient to be useful for surgically stitching wounds either manually or mechanically.