Introduction. Hematuria is a clue to the diagnosis of renal and extra renal diseases. In this survey we evaluated the prevalance of hematuria in asymptomatic adults. Methods. Non - probability convenience sampling method was applied to choose 1000 subjects among the medical staff and patients" relatives in Noor and AI-Zahra Hospitals affiliated with Isfahan University of Medical Sciences (IUMS). On the basis of inclusion criteria, urine samples of subjects were tested with dipstick and some were crossed out based on exclusion criteria. Remaining samples were centrifuged and urine sediments were examined with light microscope. Hematuric samples were divided in to glomerular and non-glomerular groups. Data analysis was performed with SPSS software package and results were statistically compared with X2 method. Results. The relative prevalance of hematuria in this study was 2.6 percent. Glomerular and non-glomerular hematuria accounted for 1 percent and 1.6 percent of cases, respectively. The origin of hematuria in younger age groups was glomerular in most cases (66.6 percent) and non-glomerular in older age groups (90 percent). There was significant difference between the prevalance of non-glomerular disease (1 percent) and those with non-glomerular origin (P < 0.001). In subjects with non glomerular hematuria who underwent urological workup, 62.5 percent were diagnosed with a specific disease. Given their normal hematologic and serological test resultes, kidney biopsy was not indicated for subjects with glomerular hematuria. All of these subjects had isolated hematuria. The pre valance of hematuria evaluated with dipstick was significantly different from the results obtained from microscopic examination of urine specimens (P < 0.001). Discussion. Most cases of hematuria were non-glomerular origin in patients older than 50 years and glomerular in younger age groups. The diagnosed diseases did not affect, the subjects prognosis and this way of patient screening do not seem to be cost-effectiveness. More extensive evaluation are essential in high risk groups and individuals older than 50 years.