Abstract: [Objective] To investigate the clinical effect and sagittal mechanical properties of zero-profile interbody fusion system(Zero-P) in single-segment anterior cervical discectomy and fusion (ACDF). [Methods] Totally, 35 patients who underwent ACDF with Zero-P cage screw devices were enrolled in present retrospectively study. The parameters including cervical lordosis (CL), operative segmental lordosis (OL), anterior interbody height (AIH) and posterior interbody height (PIH) of fusion segment were extracted for further analsis. [Results] A total of 35 patients (19 males and 16 females) were enrolled with 52.5±9.4 years old. The period of following up was 23.3 + 13.4 months. CL increased from 18.3 + 8.4 degrees pre-operation to 19.2 + 10.7 (p > 0.05) at initial follow-up and 23.1 + 7.1 at last follow-up (p < 0.05); OL was 8.2 + 4.5 before operation, increased to 14.2 + 5.1 (p < 0.01) and 11.2 + 5.2 (p < 0.05) at initial and last follow-up, respectively. The degree of OL lost with increasing length of follow-up (p < 0.05); preoperative AIH was 33.2 + 4.6 mm, increased to 36.6 + 4.7 at initial follow-up(p < 0.05) and 35.1 + 4.8 mm at last follow-up(p > 0.05), respectively; In addition, the postoperative height of PIH at initial follow-up and last follow-up were both increased, but no significant difference was found between preoperative and preoperative PIH (p>0.05). [Conclusions] ACDF with zero-profile interbody fusion system could achieve high fusion rate and significantly improve the physiological lordosis of C2-7 cervical spine; However, they were not capable of maintaining intervertebral height of cervical. It suggested that it should be cautious to select this device in patients with significant intervertebral height lost, or high requirement of postoperative stability.