OBJECTIVE To report the incidence, clinical features, causative organisms, and visual outcomes associated with delayed-onset pseudophakic endophthalmitis. METHODS We retrospectively reviewed the clinical records and microbiology files of all patients with culture-proven endophthalmitis that was present 6 weeks or more after cataract extraction and posterior chamber intraocular lens (IOL) implantation who were treated at King Khaled Eye Specialist Hospital (KKESH) during a 10-year period. RESULTS From January 1997 through December 2006, 17 patients with culture-proven, delayed-onset pseudophakic endophthalmitis were treated at KKESH. Of the 17 cases, only 5 cases developed delayed-onset endophthalmitis, among 29,509 cataract surgeries performed at KKESH, indicating an incidence rate of 0.017% (5/29,509). The mean time between cataract surgery and diagnosis of endophthalmitis was 5+/-2.48 months. The culture isolates revealed Propionibacterium acnes in 7 (41.2%) eyes, polymicrobial (mixed) infections in 3 (17.6%) eyes, Staphylococcus species in 3 (17.6 %) eyes, fungal infections in 3 (17.6%) eyes, and Alcaligenes xylosoxidans in 1 (5.9%) eye. The mean follow-up period was 29.8 months. The final visual outcomes were as follows: 7 eyes (41.2%) achieved a final best-corrected visual acuity of >or=20/60; 6 eyes (35.3%) achieved a best-corrected visual acuity of <20/60 to >or= count fingers; 2 eyes (11.8%) had hand motion to light perception vision; and 2 eyes (11.8%) were enucleated. CONCLUSIONS In this study, infection by P acnes was the most common cause of delayed-onset pseudophakic endophthalmitis and had the most favorable visual outcome, whereas fungal endophthalmitis had the worst visual prognosis.