BACKGROUND: Hemoglobin A1c (HbA1c) is a useful marker for the diagnosis and monitoring of diabetes, which has resulted in an increasing dependency on HbA1c levels for diagnosing diabetes in small- and medium-sized hospitals. We evaluated a high performance liquid chromatography (HPLC) based HbA1c autoanalyzer Bio-Rad D-10 (Bio-Rad Laboratories, USA) by comparing the analysis results with that by Tosoh HLC-723 G7 (Tosoh Corporation, Japan). METHODS: The Bio-Rad D-10 autoanalyzer was evaluated for its precision, linearity, and carryover. The analysis time and correlation were evaluated and compared with those by Tosoh HLC-723 G7 autoanalyzer. RESULTS: Bio-Rad D-10 showed within-run, between-day, and total precision of less than 1.3% coefficient of variation (CV) and excellent linearity between HbA1c in the range of 3.2%-21% (coefficient of determination, R 2 = 0.998). The sampleto-sample carryover was 0.57%. The results obtained by using Bio-Rad D-10 showed good correlation (r = 0.997; P < 0.001) with those by Tosoh HLC-723 G7; however, the analysis time using Bio-Rad D-10 was about 2.3 times per 10 samples and 2.5 times per 20 samples than those using Tosoh HLC-723 G7. CONCLUSIONS: Bio-Rad D-10 showed good performance in assaying HbA1c. Bio-Rad D-10 autoanalyzer would be suitable for use in laboratories with small to medium amount of samples to be analyzed, but its initial analyzing time was longer than that by Tosoh HLC-723 G7.