A cross-sectional study was performed from November 2005 to July 2007 to determine the prevalence of microalbuminuria and its risk factors among type 2 diabetic patients.. Two hundred and eighty-eight type 2 diabetic patients (141 males and 147 females) referred to Yazd diabetes research center were randomly recruited for the study. Microalbuminuria was detected by measuring the albumin to creatinine ratio in the early morning urine. Microalbuminuria was diagnosed if this ratio was between 30 and 300 mg/g on two occasions during three months. Prevalence of microalbuminuria was 14.2%. Chi-square analysis revealed that microalbuminuria was correlated with the diastolic blood pressure (P = 0.003) and the duration of diabetes (P = 0.000). No statistically significant correlation was found between microalbuminuria and age, sex, body mass index, levels of fasting blood sugar, glycosylated hemoglobin (HbA1c), serum triglyceride, and serum cholesterol, or systolic blood pressure. For 240 patients for whom the duration of diabetes was known from the answers in their questionnaires, logistic regression was used for analysis. Results showed that two variables including the duration of diabetes and Diastolic Blood Pressure (DBP) play a role in this model and the following Logic association was obtained: g; (x) = -9.233 +/- 0.079 DBP +/- 0.114 duration according to this model, both DBP and duration of diabetes were directly correlated with microalbuminuria. Determination of the urine albumin to creatinine ratio is an easy method for screening of microalbuminuria that is suggested for all diabetic patients, especially diabetic patients with hypertension and long-term diabetes.