Abstract:[Objective] To introduce the surgical techniques and preliminary clinical results of unilateral open-door laminoplasty com- bined with reattachment of posterior muscle for upper cervical ossification of posterior longitudinal ligament (OPLL) . [Methods] From March 2015 to March 2019, 16 patients with multiple levels of OPLL involving C2 or upper underwent unilateral open-door laminoplasty combined with reattachment of posterior muscle. After exposing C1~7 bilateral lamina and facets, the C1~7 spine processes were removed with holes punched on base of C4 and C6. Bilateral bone slots on C3~7 were made, with total bone removed on the right side, while outer bone corti- cal removed on the left side. Subsequently, the lamina in a whole was carefully raised on the right side about 1.5 cm, and fixed with mini tita- nium plate on C3, C5 and C7, while suture tie on the C4 and C6. The C2 total laminectomy was conducted, and bilateral pedicle screws were in- serted with a transvers plate fixed on the C2. Finally, the posterior cervical muscle was sutured on the C2 plate to reconstruct the attachment of the muscle. [Results] All the patients had operation performed successfully. At the latest follow up, the VAS and JOA scores significantly improved compared with those preoperatively (P<0.05) , while the cervical range of motion remained unchanged significantly (P>0.05) . [Conclusion] This unilateral open- door laminoplasty combined with reattachment of posterior muscle does effectively relieve the clinical symptoms, avoid postoperative head-up weakness, and achieve satisfactory clinical outcomes for upper cervical OPLL.