Ophthalmomyiasis interna infestation by fly larva can present in various forms. A 3-year-old girl with a 15-day history of pain, redness, and tearing of the right eye was referred to our clinic with the diagnosis of enclophthalmitis associated with an intraocular foreign body, based on clinical and ultrasonographic findings. The patient underwent pars plana vitrectomy, during which an 8-mm long larva was encountered within the vitreous cavity. It was removed and identified as a cattle botfly. The patient developed a retinal detachment 1 month postoperatively, but the family refused further treatment and the patient was lost to follow-up. Ophthalmomylasis should be included in the differential diagnosis of endophthalmitis and intraocular foreign bodies in patients from rural areas.