We evaluated the clinical usefulness (leukocyte distribution classification, morphologic classification, and morphologic flags) of the following four hematology analyzers: CELL-DYN Sapphire (CD-Sapphire) (Abbott Diagnostics, Santa Clara, CA, USA), ADVIA 120 (Bayer Diagnostics, Tarrytown, NY, USA), Beckman Coulter LH 750 (Beckman Coulter, Miami, FL, USA), and Sysmex XE-2100 (TOA Medical Electronics Co., Kobe, Japan). Four hundred thirty samples from patients and 100 samples from healthy individuals were analyzed. For distributional classification, the sensitivity rates of CD-Sapphire, ADVIA 120, LH 750, and XE-2100 were 93.1, 95.9, 94.9, and 94.9%, respectively, and the efficiency rates were 80.7, 81.6, 84.1, and 84.2%, respectively. For morphologic classification, the sensitivity rates of CD-Sapphire, ADVIA 120, LH 750, and XE-2100 were 88.6, 93.2, 77.3, and 94.3%, respectively, and the efficiency rates were 80.9, 73.0, 79.5, and 74.2%, respectively. Comparing the findings in different morphologic flags, XE-2100 showed the highest sensitivity for Blasts flag (90.9%); CD-Sapphire showed the highest sensitivity for Immature granulocytes and/or Left-shift flag (85.5%); ADVIA 120 showed the highest sensitivity for Atypical lymphocytes flag (60.0%); and LH 750 showed the highest sensitivity for Nucleated RBC flag (75.0%). Our results demonstrate that the four analyzers are comparable in overall performance.