AIM: To report the demographic and systemic characteristics of patients, clinical progression of endophthalmitis, and the efficacy of various treatment strategies, with a focus on identifying key factors for preserving vision in eyes with endogenous endophthalmitis due to Klebsiella pneumoniae (K. pneumoniae) liver abscess. METHODS: In this single-center, retrospective case series of 18 patients with endogenous endophthalmitis due to K. pneumoniae liver abscess were analyzed. Ophthalmologic features of endophthalmitis at early, intermediate and advanced stages were obtained from eyes with endophthalmitis of different severities. Prompt vitrectomy was considered primarily for all eyes except for very early endophthalmitis. Intravitreal injections of antibiotics were performed in eyes with endophthalmitis in the very early stages and in eyes where vitrectomy was not available, and additional control of infection was needed after vitrectomy. Evisceration was performed in eyes with corneoscleral perforation, advanced endophthalmitis, perforation with preseptal or orbital cellulitis, uncontrolled infection, or severe pain with no vision. RESULTS: Mean (±standard deviation) age of the 18 patients with endophthalmitis was 64.5±12.2 (range: 32-84)y, and 14 patients (77.8%) were males. Endophthalmitis tended to involve the retinal parenchyma first and then progressed into the vitreous cavity and anterior segments. However, it presented a tendency to cause massive subretinal abscesses even after vitrectomy with silicone oil tamponade. Very high intraocular pressure with new vessels on the iris (41.7%) were also commonly observed. Although all but three patients had systemic disease such as diabetes or hypertension, visual prognosis after treatment did not appear to depend significantly on underlying comorbidities. A final best-corrected visual acuity better than 20/60 was achieved only when lesions were detected very early, with relatively good initial visual acuity, likely reflecting lower bacterial inoculation in the eye. CONCLUSION: Detection of early endophthalmitis lesions appears to be the only way to preserve good vision in patients with K. pneumoniae liver abscesses. Therefore, proper guidelines for ophthalmologic screening remain to be established for subjects at a high risk of endophthalmitis.