Objectives: The aim of this study was to investigate the properties of a bioabsorbable poly-lactic acid (PLLA) membrane for guided tissue regeneration (GTR) therapy and to compare them to those of a commercial available bioabsorbable poly-lactic acid/glycolic acid copolymer (PLGA) membrane and a commercial available expanded polytetrafluoroethylene (e-PTFE) membrane. Methods: The mechanical qualities of membranes such as contact angle and tensile strength were evaluated in vitro. The passage rates of human gingival fibroblasts through the membranes were investigated for up to 5 months. The number of human gingival fibroblasts on the surface of membranes was measured for 21 days. The efficacy of those membranes for periodontal regeneration when applied on periodontal defects was evaluated in beagle dogs. Results: The occlusive effect of the PLLA membrane was kept for 5 months, while the corresponding effect of the PLGA membrane was limited for 21 days in vitro. The number of human gingival fibroblasts on the surface of the PLLA membrane was higher than that of the PLGA and e-PTFE membrane. The data on contact angle and tensile strength of the PLLA membrane were similar to those of the PLGA membrane. The histological observation showed no significant differences in the amount of epithelial down growth, the amount of new cementum and bone formation between the PLLA and PLGA membrane. Conclusions: These results suggest the possibility of clinical application of the PLLA membrane for GTR and guided bone regeneration. This study was supported by GRANT-IN-AID FOR SCIENTIFIC RESEARCH (12307051) and GC Corporation.