<p><b>OBJECTIVE</b>To evaluate the glycemic excursions in well-controlled (HbA1c<7%) patients with type 2 diabetes mellitus.</p><p><b>METHODS</b>Thirty-two patients with type 2 diabetes whose HbA1c were<7% underwent CGMS (continuous glucose monitoring system).</p><p><b>RESULTS</b>The highest blood glucose value was in 1.7 h after breakfast. The time duration for blood glucose levels of 7.8 mmol/L, 11.1 mmol/L and 13.9 mmol/L were 28%, 13% and 6%, respectively. The area above 7.8 mmol/L in blood glucose curve was significantly correlated with HbA1c levels. Asymptomatic hypoglycemia and continuous hyperglycemia (BS>13.9 mmol/L more than 2 hours) were also found in the study.</p><p><b>CONCLUSION</b>The apparent hyperglycemia exists in well-controlled type 2 diabetic patients, and CGMS is useful in assessment of glycemia.</p>