High grade proteinuria in allograft glomerular diseases is concerned with the reduced function and shortened su/Vival of kidney allograft. Monitoring changes in glomerular filtration rate (GFR) by serum creatinine and cystatin C are the recommended methods for assessing the progression of kidney allograft function with proteinuria. Materials and Methods: Sixty renal transplanted patients with allograft su/Vival of at least 1 year, with proteinuria were included in the study. All patients had baseline routine clinical care including age, sex, weight, body mass index, serum creatinine (Scr), serum cystatin C (ScysC), urine creatinine, proteinuria at the same day. the authors established the correlations of these pairs: between creatinine clearance (Clcr24h) and serum creatinine, between Clcr24h and serum cystatin C, and between Clcr24h among four estimated GFR formulas (Cockcroft Gault, MDRD, CKD-EPI and Le Bricon formulas). Results: THe mean ScysC, Scr and Clcr24h were 1.49 :t 0.51 mg/L, 1.26 +/- 0.25 mg/dL and 56.03 +/- 20.74 ml/min/1.73m2 respectively. There were significant correlations between Clcr24h and 1/ScysC (r1=0.775 (p0.000)) and Clcr24h and 1/Scr (r2