This is a retrospective study in consecutive cases with cultured-proven endogenous endophthalmitis (EE) treated at the largest tertiary medical center in middle Taiwan in the past 10 years. 83 eyes of 70 patients were enrolled. The mean interval between systemic diseases to the diagnosis of EE was 8.84 ± 6.94 days. The mean initial visual acuity (VA) in the logarithm of minimal angle of resolution (logMAR) was 1.63 ± 0.87. Type 2 diabetes mellitus was the most common predisposing medical illness (N = 53, 63.86%). The most common infectious sources were intra-abdominal abscess (N = 36, 43.37%), and the second most reason was urinary tract infection. The causative pathogen was Gram-negative predominant (N = 64, 77.11%). After aggressive treatment, 34.94% of eyes regain useful vision, and only six eyes underwent enucleation or evisceration. The binary multivariate logistic regression model revealed that female gender (95% CI 1.002-19.036, p = 0.05, OR 4.37), initial VA logMAR (95% CI 0.089-0.550, p = 0.01, OR 0.22), and more intravitreal injections (95% CI 0.368-0.927, p = 0.023, OR 0.58) were independent risk factors influencing final outcomes. Based on the results mentioned above, early diagnosis is recommended to gain better outcomes. The mean interval between systemic diseases to the diagnosis of EE was 8.84 ± 6.94 days in our sample population, clinicians should maintain a higher index of suspicion during this period when encountering patients with bacteremia or fungemia.