Objective To study the course of different cervical nerve segments and their related intervertebral foramen’s size so as to increase safety and decrease complications in microinvasive surgery for cervical syndrome. Methods Fifteen human cervical specimens (30 sides) were anatomically observed for the course, branches and distribution of cervical nerves. Results The diameter of intervertebral foramen ranges from 0.54 to 0.65 cm, and increases gradually from top to bottom. The vertical diameter and anteroposterior diameter between C4, C5 and C6 vertebrae are smaller, and those between C3 and C7 are larger, but the diameter line of nerve root in intervertebral foramen from up to down gradually increases. The anteversion angle between nerve root and spine cord on horizontal plane is from 15? to 19?, within a small variation, while the declination angle on coronal plane gradually decreases from C3 to C7. There exist plenty of anastomosis branches among the cervical dorsal rami. Conclusion In the range of 0.6 cm around articular process at the entrance of intervertebral foramen, it is the narrowest part, the removal of which may alleviate the pressure on nerve root and benefit spinal stability. Because of the general existence of anastomosis branches of cervical nerve, the symptoms of cervical syndrome are not completely consistent to innervation. The intervertebral foramen between C4, C5, C6 is relatively small and the diameter line of nerve root is comparatively large, so the nerve root at C4, C5, C6 is most likely to be pressed.