Regeneration of dura mater of the brain is one of the most urgent tasks in the fields of regeneration medicine, considering the facts that we have many patients infected with fatal Creutzfeldt-Jakob disease following transplant of dried dura mater in the brain operations. Hence we designed the artificial dura mater made from poly(L-lactic acid-co-glycolic acid-co-ε-caprolactone). The sutured substitutes have the ability to prevent the leakage of cerebral fluid, would be absorbed in several months and the patient might be free from the possible side effects caused by the implanted materials. The leakage-proof tests for the developed substitutes were carried out and it was demonstrated that the sutured substitutes and dura mater support the pressure of saline as large as 400mmAq without leakage. The dural regeneration experiments were carried out with rabbits and successful regenerations of dura mater were observed. No inflammations were observed around the substitutes throughout the experimental period till the complete absorption of the materials.