Purpose Streptococcal gangrene, also termed streptococcal necrotizing fasciitis, is resurgent but remains exceedingly rare. Ophthalmologists and dermatologists must be aware of streptococcal gangrene, as eyelids are the most commonly affected area of the head and neck. Methods We studied two cases of streptococcal gangrene of the orbit with clinical manifestations indistinguishable from common nonnecrotizing orbital cellulitis. Results Infection progressed with dramatic rapidity to produce eyelid necrosis, respiratory failure, sepsis, and severe permanent visual loss caused by ophthalmic artery occlusions. Histopathologic analysis disclosed vascular thrombosis, necrosis, acute inflammation, and the presence of gram-positive cocci. Cultures grew heavy group A beta hemolytic Streptococcus. The first patient was infected with M type 1 carrying exotoxins A and B. The second patient was also infected with Streptococcus carrying exotoxin A. Conclusion Early diagnosis of this life-threatening infection is of paramount importance because survival may depend on early surgical debridement.