PURPOSE: Trapdoor orbital blowout fracture is most common in orbital blowout fracture. Various materials have been used to reconstruct orbital floor blowout fracture. Absorbable alloplastic implants are needed because of disadvantages of nonabsorbable alloplastic materials and donor morbidity of autogenous tissue. The aim of the study is to evaluate usefulness of absorbable mesh plate as a reconstructive material for orbital blowout fractures. METHODS: From December 2008 to October 2009, 18 trapdoor orbital floor blowout fracture patients were treated using elevator fixation, depressor fixation, or elevator-depressor fixation techniques with absorbable mesh plates and screw, depending on degree of orbital floor reduction, because absorbable mesh plates are less rigid than titanium plates and other artificial substitutes. RESULTS: Among 18 patients, 5 elevator fixation, 4 depressor fixation, and 9 elevator and depressor fixation technique were performed. In all patients, postoperative computed tomographic (CT) scan showed complete reduction of orbital contents and orbital floor, and no displacement of bony fragment and mesh plate. Mean follow-up was 10 months. There were no significant intraoperative or postoperative complications. CONCLUSION: Three different techniques depending on the degree of orbital floor reduction are useful for open reduction and internal fixation of trapdoor orbital floor blowout fracture with absorbable mesh plates.