This study is to clarify whether obesity status affects glycated albumin (GA) and HbA1c levels in adults with type 2 diabetes. One hundred and seven individuals with type 2 diabetes without advanced complications participated in this study. The relationship between HbA1c, GA, hemoglobin (Hb), albumin (ALB), absolute value of GA (aGA) and Body Mass Index (BMI) were examined using Pearson's correlation coefficient. The comparison of each parameter was conducted using unpaired t-test between the obese (BMI> or =25) and the non-obese (BMI<25) group. Additionally the multiple regression analyses to find factors related with GA (i.e. BMI, HbA1c, age, ALB and the insulin therapy) were performed. HbA1c level and BMI showed very weak correlation (r=-0.04; p=0.65). However, GA, aGA and BMI showed a significant negative correlation (r=-0.28; p=0.004, r=-0.22; p=0.024). The GA and aGA values of the obese group were significant lower than those in the non-obese group. In multiple regression analysis, BMI (beta=-0.24; p=0.001) was negatively, and HbA1c (beta=3.65; p<0.001) was positively correlated with GA. In conclusion, the current analysis demonstrated a need of careful evaluation of GA values in obese diabetic patients in daily practice. Further researches are required to elucidate the underlying mechanisms.