Abstract： Objective To investigate the prognosis of two decompression approaches for cervical spondylotic myelopathy. Methods 86 cases were divided into two groups. 40 cases were underwent decompression by anterior decompression, fusion and internal fixation with titanium screws and plate and 46 cases underwent posterior single opendoor laminoplasty. To investigate the prognosis of two decompression approaches for single compressive segment, two compressive segments, three compressive segments and four compressive segments. Results All cases were followed up for 20 ～ 73 months with an average of 43 months. The mean JOA recovery rate was significant different between single compressive segment group (P ＜ 0.05), and no significant difference between two compressive segments and three compressive segments(P ＞ 0.05), and significant difference between four compressive segments groups (P ＜0.05). Conclusion For single compressive segment, the anterior surgery has a good surgical result,for two or three compressive segments, anterior and posterior surgery had same effect, for the four compressive segments, posterior surgical effect was good.