Coloboma is a genetic disorder which occurs due to a defect in the eye structure such as iris, lens, choroid plexus or optic disc. In this report, coloboma with posterior synechia in the right eye and iris prolapse in the left eye of a kitten are reported. A two-month-old female domestic short-hair cat with discrete from eyes, hyperemia, purulent discharge and photophobia was referred to the Small Animal Teaching Hospital of the Faculty of Veterinary Medicine, University of Tehran. In clinical examination of the eyes, the lack of lateral part of the upper eyelid and posterior synechia in the right eye and iris prolapse in the left eye were found. Bacterial conjunctivitis was detected as well. The kitten case history showed a hereditary reason for the right eye deficiency and a traumatic reason for the left eye iris prolapse. Eye examination revealed no other hereditary disorders. Because of the limited disorder of the right eyelid, treatment was based on topical antibiotic and anti-inflammation drugs. Surgery was performed to treat the left eye iris prolapse. The present case is the first report of coincidence of upper eyelid coloboma with posterior synechia in cat in veterinary literature.