The objective of this study is to assess the change trends of perioperative esophageal area for anterior cervical corpectomy fusion (ACCF) and to analyze the risk factors of the area for postoperative dysphagia. We retrospectively analyzed 309 patients who underwent ACCF due to degenerative cervical diseases between November 2015 and September 2019 at our hospital. Patients were divided into 2 groups named the dysphagia group and the normal swallowing function group, according to the swallowing function after ACCF. The esophageal area was measured at T1 level using computed tomography axial plane images before and after surgery (1 week, 1 month, 8 months, and 12 months), in order to assess the change trends of esophageal area perioperatively and analyze risk factors of the area for dysphagia after ACCF. The area was highest at 1 week after surgery and would be decreased over time in both groups, which was recovered to the preoperative levels in 12 months after surgery. The incidence of dysphagia after ACCF was 41.1%. In the dysphagia group, 127 patients (mean age 59.299 years) had dysphagia after ACCF. In the normal-swallowing function group, 182 patients (mean age 59.8352 years) had normal swallowing function after ACCF. The preoperative esophageal area was larger in the dysphagia group than in the normal-swallowing function group. Preoperative esophageal area was correlated with postoperative dysphagia (odds ratio: 1.3457, 95% confidence interval: 1.106-1.637). When the esophageal area at preoperation was above 3.388 cm2, the risk of postoperative dysphagia was higher. The esophageal area was the biggest at 1 week postoperatively, significantly decreased over time and would be recovered to the normal size at 12 months after surgery. Preoperative esophageal area should be considered when evaluating the risk factor for dysphagia after ACCF.