Objective To explore the application value of single-door laminoplasty via Y type nano-bone plate in treating multilevel cervical spondylotic myelopathy (MCSM) and analyze the short-term efficacy.Methods From January 2013 to December 2016,79 cases of MCSM were treated with single-door laminoplasty via Y type nano-bone plate to evaluate the improvement of post-operative neurological function by the Japanese Orthopaedic Association (JOA) evaluation system.We also measured cervical curvature of cervical X-ray and C5 sagittal diameter of the spinal canal before operation and 6 months after operation to understand the maintenance and enlargement of the spinal canal.The improvement degree of spinal cord compression was evaluated by preoperative and postoperative cervical MRI.Osseous healing on the open door side and the door shaft side was observed with the aid of three-dimensional spiral CT.Results Follow-up ranged from 6 to 36 months,with an average of (20.4±7.9)months.Preoperative JOA score was (8.6 ± 1.3) points and JOA score 6 months after operation was (14.3 ± 1.5)points (P ＜ 0.05).JOA improvement rate was (68.6 ± 15.8)％;postoperative follow-up X-ray and threedimensional spiral CT showed that the spinal canal had satisfying enlargement,the door shaft side all had osseous healing,the open door side osseous healing was not obvious,and there was no lamina collapse or reclosing.Sagittal diameter of theC spinal canal was (8.9±l.1)mm before operation and (15.1±l.1)mm 6 months after operation (P＜0.05).The spinal canal enlargement rate was (70.8±22.3)％,cervical curvature was (14.8± 7.0)°preoperatively and (15.1±6.7)°postoperatively with no significant difference (P＞0.05).Conclusion EOLP via Y type nano-bone plate is safe and efficacious in treating MCSM.It not only provides a good immediate fixation,but also provides the possibility for the open door side lateral osseous fusion.