Conventional cervical MRI is the gold standard exam for diagnosis of cervical myelopathy, but cannot detect dynamic cord compression. This study aims to evaluate radiologic factors suggesting dynamic spinal cord compression. Methods We retrospectively reviewed the patients who examined dynamic MRI in addition to conventional MRI. A total of 50 patients were included in this study, comprised of 36 in the group P (aggravation of spinal cord compression on dynamic MRI) and 14 in the group N (non-aggravation of spinal cord compression on dynamic MRI). Radiologic factors were compared. Results The following factors were analyzed: age, cervical canal diameter (CCD), spinal cord diameter (SCD), subarachnoid space (SAS), cervical lordosis (CL), cervical ROM, anterior length of cervical cord (ALCC), posterior length of cervical cord (PLCC), length of anterior column (LAC), and length of posterior column (LPC), Significant differences were found in age, CCD, SAS, CL, LPC (p<0.05). In ROC curves, age (AUC 0.813, cutoff value 54), CCD (AUC 0.858, cutoff value 10.32), and SAS (AUC 0.884, cutoff value 3.25) were a significant factor in predicting deterioration of spinal cord compression during the dynamic posture. Conclusion Dynamic MRI is more useful for the diagnosis of dynamic spinal cord compression in the following conditions: age is 54 years or older, CCD average is less than 10.32 mm, SAS average is less than 3.25 mm, CL is-1.98˚ or LPC is less than 105.45 mm.