Background:Proteinuria is a classic sign of kidney diseases and its presence carries powerful prognostic information. The fractional excretion of albumin (FEAlb) measures the percent of filtered part of albumin that is excreted in the urine. So a positive test for urinary albumin excretion could signify the need for an intensive multifactorial intervention strategy, including behavior modification and targeted pharmacotherapy, aimed at preventing further renal deterioration and improving the overall cardiovascular risk factor profile. Moreover, all levels of reduced glomerular filtration rate(GFR) should be complemented by quantification of urinary albumin to predict optimally progression to end stage renal disease (ESRD).Patients and method: In the present study we studied the correlation between daily proteinuria and fractional excretion of filtered albumin. This study was done on 20 patients with proteinuria.For all these patients; full medical history, complete clinical examination, and the following investigations were done: Serum creatinine, GFR using Cockcroft-Gault equation, Serum albumin, 24h urinary proteins and Fraction excretion of albumin; Then all patients received 20gm of human albumin/day for 2 days then the following investigations were repeated: Serum albumin, Fractional excretion of albumin and 24h urinary proteins.Results:There were correlations between FEAlb and some of other variables including 24 h urinary proteins. Also, given the threshold of proteinuria at 3 gm⁄d, the predicted FEAlb cutoff value that discriminate nephrotic from subnephrotic proteinuria that achieved the greatest sensitivity was 0.68 ,while FEAlb cutoff value that achieved the greatest specificity was 0.16 . On the other hand, at the threshold of proteinuria at 3.5 gm⁄d, The predicted FEAlb cutoff value that discriminate nephrotic from subnephrotic proteinuria that achieved the greatest sensitivity and the greatest specificity was 0.175. Conclusion:FEAlb might be used as a new strategy to discriminate nephrotic from subnephrotic proteinuria. However further widescale studies are needed to ensure the results and show new correlations.