PURPOSE To investigate the surgical outcome of grafting acellular human dermis compared with concurrent lower eyelid retractor recession during swinging eyelid orbital decompression for correction of lower eyelid retraction in patients with Graves' orbitopathy. METHODS Institutional Review Board-approved retrospective nonrandomized study of 54 Graves' orbitopathy patients (95 eyes) from 2008 to 2012. Patients who received decompression were divided into 3 groups: Group 1 with conjunctival lengthening using 0.3-mm thickness AlloDerm (36 eyes), Group 2 with inferior retractor recession (33 eyes), and Group 3 with decompression only (26 eyes). Outcome measures included lower eyelid height, inferior sclera show, cosmetic appearance, and complications. RESULTS Baseline clinical characteristics and the degree of improvement of exophthalmos were not different between groups. Preoperative MRD2 was higher in group 1 (8.0 mm) than in groups 2 (6.9 mm, p < 0.001) and 3 (6.6 mm, p < 0.001). Mean improvement of MRD2 as well as postoperative improvement of inferior scleral show at postoperative 4 to 6 months were significantly higher in group 1 (2.7 mm) than in groups 2 (1.8 mm, p < 0.001) and 3 (1.2 mm, p < 0.001). CONCLUSION Simultaneous correction of lower eyelid retraction using thin AlloDerm during swinging eyelid orbital decompression maximizes improvement of lower eyelid retraction compared with concurrent inferior retractor recession.