The management of diabetes using different methods such as diet, exercise, and medical treatment can delay the progression of diabetes and its complications. Complications of diabetes can be reduced by the careful regulation of blood glucose. Self-monitoring blood glucose enables diabetes patients to control their blood glucose levels effectively and is used globally to manage diabetes, indicating the importance of blood glucose testing. ISO 15197:2013 is an international regulation for verifying the reliability and validity of glucometers. Here, we evaluated six glucometers that were purchased randomly on the Korean market using the following verification criteria: precision evaluation, accuracy evaluation, and effect of hematocrit concentration All verifications were performed according to ISO 15197:2013. In a repeatability study, the range for the total coefficient of variation was 1.3-4.3%, 1.5-5.7%, and 1.4-3.4%, resp. In the intermediate precision evaluation, the coefficient of variation was 1.6-6.6%, 2.5-6.8%, and 1.1-3.3% for the three levels of control specimen (51-110, 151-250, 251-400 mg/dL), resp. Three glucometers met ISO 15197:2013 for the accuracy criteria, and only one glucometer met the ISO 15197 hematocrit effect. More than 80% of the evaluated glucometers did not fulfill the ISO 15197:2013 criteria, and most were affected by the hematocrit concentration These inaccurate results can increase the risk of uncontrolled blood glucose levels in diabetes patients, who should consider these limiting functions when evaluating their results. As venous blood was used in this study, further evaluations will be needed to confirm the results using capillary blood.