We report the case of a 25-year-old female, who presented with a large, pale tumor of her ciliary body that extended to >180° of the anterior chamber angle. All preoperative examinations including ultrasound biomicroscopy, scleral transillumination, and MRI indicated melanoma. A thorough systemic work-up was negative. A diagnosis of ring melanoma was suspected, and the patient was scheduled for enucleation. However, perioperative frozen section indicated granulomatous inflammation. The enucleation was cancelled, and a subtenon injection of triamcinolone was administered, which resulted in the disappearance of the tumor. Together, the findings meet the criteria for the diagnosis of isolated ocular sarcoidosis. This case demonstrates that a sarcoid granuloma can mimic all clinical features of a ring melanoma. Therefore, a biopsy should be done before destructive surgery is carried out.