The increasing prevalence of Klebsiella pneumoniae liver abscess in Asian countries is attributable to virulent strains of the K1 serotype. We investigated the risk factors for the K1 serotype K. pneumoniae liver abscess. A case-control study was performed using the database of a nationwide study of liver abscess in Korea. Multivariate logistic regression analysis was performed for 78 cases of the K1 serotype K. pneumoniae liver abscess and 81 controls with non-Klebsiella. Diabetes mellitus was the significant risk factor (OR 2.13; 95% CI 1.026 approximately 4.428; P = 0.042) for the K1 serotype K. pneumoniae liver abscess. Biliary disorders had a strong negative association (OR 0.18; 95% CI 0.078 approximately 0.410; P < 0.001). This study suggests that diabetes mellitus is a more significant risk factor for the K1 serotype K. pneumoniae liver abscess than for the non-Klebsiella liver abscess.