Purpose: The purpose of this 6-month randomized, controlled, blinded, clinical trial was to evaluate and compare the efficacy of amnion membrane (AM) with deproteinized bovine bone mineral (BBM) and a collagen membrane (CM) with BBM in guided tissue regeneration (GTR) for the treatment of intrabony periodontal defects. Materials and Methods: Ten chronic periodontitis patients with bilateral intrabony defects with radiographic evidence of intrabony component ≥ 4 mm and probing pocket depths (PPDs) ≥ 6 mm were randomly divided into two groups. The test group was treated with AM+BBM, and the control group was managed with CM+BBM. Periodontal clinical parameters were recorded at baseline and at 6 months after treatment. Results: PPD, clinical attachment level (CAL), and probing bone (PB) showed significant improvements after 6 months in both the test and control groups. Gingival recession showed a significant increase in the control group but not in the test group. The changes in mean PPD, PB, and CAL preoperatively and postoperatively between the groups were not significant. There was no significant relationship between the depth of the baseline bony defect and CAL gain. Conclusion: Both AM and CM in conjunction with BBM provided improvement of clinical periodontal parameters. AM did not induce significant gingival recession and is suggested as a new barrier membrane in GTR treatment. Keywords: amnion membrane, bovine bone mineral, collagen membrane, guided tissue regeneration, intrabony defect