It innervates the skin of the back of the upper neck and of the scalp posterior to the ear.

It arises from the (lateral branch of the ventral ramus[3][4]) of cervical spinal nerve C2;[3][4][2] it (sources differ) receives[1] or may also receive fibres from cervical spinal nerve C3.

[4] The lesser occipital nerve is one of the four cutaneous branches of the cervical plexus.

[3][4] It divides into medial and lateral segments between the inion, and intermastoid line.

[citation needed] The nerve provides sensory innervation to the upper part of the back of the neck and adjacent[6] scalp posterior to the auricle;[6][1] it may also contribute to the sensory innervation of the auricle itself.