To determine the effect of smoking on the kidneys and the microvasculature and to determine the incidence of microalbuminuria in smokers without other vascular risk factors, an analytical cross sectional study was conducted among 120 patients attending the general medicine OPD of Government Rajaji Hospital, Madurai. Non smokers were age and sex matched and taken as control group. In this study, the number of smokers with high urine albumin levels(>20mg/L) were 69(90.8%) and the number of non-smokers with high urine albumin levels were 7(15.9%). The mean urine albumin for smokers is 47.3271 mg/L and the mean urine albumin for non-smokers is 18.9402 mg/L. The chi square P value comparing theses two means is <0.001. The difference is statistically significant and this shows that smokers had significantly high urine albumin levels when compared to non-smokers.