Our first case was probably caused by a late-onset postsurgical infection, and the second case was likely owing to a foreign body invasion. Infectious necrotizing scleritis is intractable, even with fortified medical therapy. P aeruginosa, the most frequently isolated bacteria in cases of necrotizing scleritis, is virulent and capable of releasing a variety of exotoxins such as exotoxin A, exoenzyme S, and elastase, causing extensive scleral thinning and melting. Fungal infections are difficult to treat once they invade the deep scleral lamella, and the diagnosis becomes more difficult. In addition, the strength of topical antibiotic can be greatly reduced. Both of our patients resisted long-term medical treatment and required surgical intervention.