PURPOSE: To report a case of trabeculectomy associated endophthalmitis caused by penicillin resistant Streptococcus pneumoniae. METHOD: Case report. RESULTS: The patient developed endophthalmitis 1 month after an uncomplicated trabeculectomy for primary open-angle glaucoma. Vitreous cultures grew abundant, highly penicillin-resistant S pneumoniae. Despite aggressive treatment with vitrectomy and intravitreal injections of vancomycin hydrochloride and amikacin sulfate, the patient had a poor visual outcome. CONCLUSION: Penicillin-resistant S pneumoniae can cause endophthalmitis after trabeculectomy.