BACKGROUND Diabetes mellitus is a metabolic disease that is characterized by hyperglycemia. Blood glucose (BG) is helpful for the diagnosis and treatment of diabetes and an important part of the management of diabetes. Point-of-care testing (POCT) is generally used by patients themselves or medical personnel to monitor BG. The objective of this article was to evaluate the accuracy and consistency of POCT on venous blood samples and compare it with the central laboratory system to determine the reliability of POCT measurement results as diagnostic criteria. METHOD A total of 162 venous whole blood samples were pooled in this study, which included different concentrations and were determined by three POCT systems randomly. The results were compared with the central laboratory system, which uses the Glucose GOD-PAP method (HITACHI 7600-120). The accuracy was evaluated by the International Organization for Standardization (ISO) 15197:2013. RESULT Bland-Altman and Passing-Bablok regression analysis showed three POCT systems that were comparable with the reference method (0.65, 95% CI: -0.57 to 1.86, Y = -0.11 + 0.95X for ACCU-CHEK® Performa; 0.40, 95% CI: -1.3 to 2.1, Y = 0.036 + 0.96X for ACCU-CHEK® Active; 0.70, 95% CI: -0.44 to 1.83, Y = -0.073 + 0.95X for OneTouch ® UltraVue). According to ISO 15197:2013, all POCT systems showed 100% of the results within 0.83 mmol/l (15 mg/dl) at BG concentrations <5.55 mmol/l (100 mg/dl); 92%, 89.2%, and 95.7% of the measurement results within 15% at BG concentrations ≥5.55 mmol/l (100 mg/dl) for ACCU-CHEK® Performa, ACCU-CHEK® Active, and OneTouch® UltraVue, respectively. CONCLUSIONS The POCT system cannot replace the central laboratory system as a provider of a standard result in clinical diagnosis. It can only be used as a screening test.