Background: Smoking has been associated with the prevalence, development, and progression of kidney disease. The effect of smoking on kidney function in healthy population is unclear. Objective: to examine the relationship between smoking and indicators of kidney damage in a healthy population without diabetes mellitus or hypertension. Methods: This is a cross sectional case-control study. Our study sample was 190 subjects (100 cases&90 controls). They were tested for indicators of kidney damage : renal impairment by Cockroft-Gault estimated GFR less than 60ml/min/1.73m2 and proteinuria by urine protein- creatinine ratio of 0.20mg/mg or greater. Results: This study shows that smoking is associated with renal impairment in the healthy population. The relation between smoking and proteinuria is less clearConclusion: There is a relation between smoking and renal impairment. A dose-response effect on GFR was shown with lifetime exposure to smoking. The relation between smoking and proteinuria was less significant.