Six muscles are responsible for eye movements. These are four rectus muscles: medial, lateral, inferior, and superior rectus and two oblique muscles: superior and inferior. All these muscles originate from the common ring tendon (annulus of Zinn) at the posterior segment of theorbit. Of the four rectus muscle, medial rectus muscleis the thickest and strongest ocular muscle. It produces adduction of the eyeball. Lateral rectus muscle is long and thin, its contraction produces abduction of the eyeball. The lateral rectus has the longest arc of contact, making faden procedure on this muscle ineffective. Superior rectus muscle runs forward above the eyeball together with levator palpebrae muscle with which it is closely connected by fascial capsules. Its contraction produces elevation of the eyeball, slight adduction, intorsion. Inferior rectus muscle produces depression of the eyeball, adduction, and extortion. Superior oblique muscleis the longest ocular muscle. It arises from the lesserwing of the sphenoid bone. Contraction of this muscle produces depression of the eyeball, abduction of the eyeball (vertical axis), intorsion. Inferior oblique Muscleruns from lacrimal fossa in the lower part of the orbit passes backward and to the temple under the inferiorrectus muscle and inserts in sclera below this muscle. Contraction of the inferior oblique muscle produces eyeball elevation, most prominent at abduction, abduction (vertical axis), and extorsion. Muscles are mainly supplied by the ophthalmic artery. Ocular veins run similarly to the arteries. In the orbit, eyeball together with extraocular muscles is supported by a complex of fibroelastic structures withfatty lining.