Obliquus capitis inferior is one of the muscles of the suboccipital triangle of the neck. It arises from the spinous process and adjacent lamina of the axis bone (C2) of the vertebral column. It ascends superolaterally to insert into the posteroinferior surface of the transverse process of the atlas (C1).
It is innervated by the suboccipital nerve, the dorsal ramus of the first spinal nerve (C1).
Obliquus capitis inferior acts to rotate at the atlanto-axial joint. Acting unilaterally, it turns the face to the ipsilateral side.