Levator labii superioris is one of the muscles of facial expression. It must not be confused with another muscle, levator labii superioris alaeque nasi - see submenu. A broad, flat, quadrangular muscle, it may be considered as three parts extending between the lateral side of the nose and the zygoma in the infraorbital area:

• angular head:
  • origin from superomedial part of frontal process of maxilla
  • most medial head
  • fibres pass inferolaterally
  • forms two parts inferiorly:
    • medial part inserts into greater part of nasal alar cartilages and nasal skin
    • lateral part merges with the superior border of orbicularis oris
• intermediate head:
  • origin from inferior part of orbit just superior to infraorbital foramen
  • passes directly downwards
  • inserts by merging with more lateral fibres of orbicularis oris than angular head
• lateral head:
  • origin from malar surface of zygomatic bone
  • fibres pass inferomedially
  • inserts by merging with more lateral fibres of orbicularis oris than intermediate head

Levator labii superioris has a blood supply derived from the facial artery.

It is innervated by the the buccal branch of the facial nerve (CN VII).

Levator labii superioris muscle acts to raise and evert the upper lip.