The present invention relates to a medical composite biomaterial. More specifically, the present invention relates to a medical composite biomaterial including collagen and a hyaluronic acid derivative. Also, the present invention relates to a cartilage cell treating agent using the biomaterial and stem cells derived from a mammal umbilical cord. The biomaterial does not cause an immune reaction, has superior durability, and the cartilage cell treating agent comprising the biomaterial and the stem cells enables arthroscopic surgery, thereby reducing pain of the patient and effectively treat of degenerative arthritis and cartilage damage.
