It is part of the three sections of the occipitofrontalis muscle which covers parts of the head. The other two parts are the Occipitalis muscle and the Galea Aponeurosis muscle.

The Frontalis muscle is located above the eyebrows and along the forehead. The function of the Frontalis muscle is to allow people to change their facial expressions. The Frontalis muscle is thin, has four sides, and it closely adheres to the superficial fascia (skin). It is what allows the eyebrows to raise and the forehead to wrinkle. It is broader than the Occipitalis muscle.

The muscle has no bony attachments. It is attached to the skin of the eyebrows. The lateral fibers of the Frontalis muscle are blended with the Orbicularis oculi muscle over the zygomatic process of the frontal bone.

The primary function is to lift the eyebrows especially when looking up. It also acts when when a view is too distant or dim. From these attachments the fibers are directed upward, and join the Galea Aponeurotica below the coronal suture. The medial margins of the Frontalis muscles are joined together for some distance above the root of the nose; but between the occipitales there is a considerable, but variable interval, occupied by the Galea Aponeurotica. It has a very distinctly heart-shaped upper edge that reduces down toward the bridge of the nose and then stops immediately superior to the eye sockets.