Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that affects many body tissues and leads to major morbidity and mortality. Renal disease in RA is clinically important because it restricts the management of primary disease and increases mortality. The objectives of this study are to (1) investigate the difference between RA patients with and without microalbuminuria (MAU) and (2) find out the relation between MAU and disease activity as well as subclinical cardiovascular effects. Ninety RA patients were divided into two groups according to the presence of MAU, in addition to 30 healthy volunteers. ESR, hs-CRP, RF, lipid profile, urinary microalbumin, GFR, renal function tests, carotid intima media thickness (cIMT), flow-mediated dilatation of the brachial artery (FMD), ECG, and echocardiographic examination were performed for patients and controls. MAU positive RA patients revealed significantly higher lipid profile, ESR, hs-CRP, DAS 28, cIMT, and lower FMD as well as ECG and echocardiographic abnormalities compared to MAU negative RA patients. Moreover, there was significant positive correlation between MAU and DAS28, hs-CRP, LDL, cIMT as well as negative correlation with FMD%. In our study, all RA patients with MAU had a normal serum creatinine concentration and gave a negative result with Albustix. MAU is significantly correlated with ESR, hs-CRP, lipid profile, cIMT, and FMD% in RA patients; therefore, it can be used as an index to measure disease activity as well as subclinical cardiovascular affection in RA patients.