Only a few isolated cases of endophthalmitis have Corynebacterium been implicated as etiology. This diphtheroid, which has been considered for a long time as a nonpathogenic contaminant from the conjunctival flora, may produce systemic diseases usually in immuno-deficient patients. Keratitis and endophthalmitis cases have been reported in the literature. We report three cases of chronic endophthalmitis after extracapsular extraction with intraocular chamber posterior lens which are characterized by many subacute iridocyclitis and vitritis attacks treated by topical steroids. These endophthalmitis are characterized by decrease of visual acuity, hypopion, white plaque on posterior capsule and vitritis. In the first case, Corynebacterium has been isolated from the culture of vitreous and in the second and third cases from the culture of aqueous humor. These bacteria are often very slow growing, 8 to 14 days in the 3 cases. Colonies may not become visible on culture plates before one week or more. Corynebacterium grow well on ordinary media (blood and chocolate agar). The major difficulty is not to discard organism frequently considered contaminants. The treatment associated systemic antibiotherapy with steroids or not, central capsulotomy and vitrectomy with intraocular injection of antibiotic with or without steroids. Antibiotics sensitivities among diphteroids vary greatly. Quinolones, penicillins, vancomycin, cyclines and aminosides are often a good choice. However, individual sensitivities determined by the antibiogram must be used for an appropriate treatment.