BACKGROUND: We evaluated the performance of the TOSOH glycohemoglobin analyzer HLC-723GHb V A1c 2.2TM (TOSOH Corp. Kyoto, Japan), a recently introduced automated hemoglobin A1c (HbA1c) analyzer using high performance liquid chromatography (HPLC) method without sample pretreatment. METHODS: The performance characteristics evaluated were precision, linearity, comparison with VARIANTTM (Bio-Rad, Germany) and throughput following NCCLS evaluation protocols (EP5-T2, EP6-P, and EP9-T). RESULTS: The within-run and between-day CV's were 0.910 and 1.328 for low level (6.2%), 1.214 and 1.460 for middle level (8.5%), and 0.789 and 1.449 for high level (10.7%), respectively. We found the perfect linearity of HbA1c (%) from 6.5 to 10.2 (r2=0.9995). Comparison studies between A1c 2.2 and VARIANTTM yielded the following correlation equations; A1c 2.2TM = 0.9915 (VARIANTTM) + 0.1198 %HbA1c (r=0.9936, P < 0.0001). Throughput was 28.0 tests per hour for A1c 2.2TM compared with 15.2 tests for VARIANTTM, which were determined including red blood cell lysis time before sample loading for VARIANTTM. A1c 2.2TM did not need sample pretreatment. CONCLUSIONS: With the above results, A1c 2.2TM shows acceptable performance and is suitable for routine use in the clinical laboratory.