Idiopathic membranous nephropathy is the most common form ofnephrotic syndrome in adults. The immune-mediated glomerular injury inmembranous nephropathy is associated with increased production of tumornecrosis factor alpha (TNF-α) which may play a contributory role. The aim of our work is to explore the role of pentoxifylline therapy onthe level of tumor necrosis factor alpha (TNF-α) in patients with idiopathicmembranous nephropathy and the beneficial effect on proteinuria, serumalbumin after administration of pentoxifylline. We studied 3 groups, Group 1 included 10 patients with idiopathicmembranous nephropathy; they received Pentoxifylline (Trental) 1200 mg perday with anti hypertensive anti proteinuric agents plus lipid lowering agents.Group II included 10 patients with idiopathic membranous nephropathy; theyreceived anti hypertensive anti proteinuric agents plus lipid lowering agents.Group III (Normal control group) included 10 subjects with normal clinical andlaboratory investigations. Patients were subjected to Full history taking , clinicalexamination and laboratory investigation including Complete blood picture,Liver function tests, Kidney function tests, Serum cholesterol, urine analysis, 24hours urinary proteins, Tests to exclude secondary membranous nephropathyas(HBV, HCV antibody, ANA, C3), Renal biopsy (light microscopy) done todiagnose membranous nephropathy and Measurement of tumor necrosis factoralpha (TNF-α) in blood and urine initially at the start of the study for 3 groupsand 3 months thereafter for group I and group II. We found that urinary TNF-α was positively correlated with proteinuria(p=0.05). We also found that TNF-α was significantly higher in the studygroups (group I and group II) in comparison to the control group. By comparingthe effect of treatment on both groups, we found that there was tendencytowards higher serum albumin in group I than in group II, although this wasstatistically insignificant. There was tendency to lower 24 hrs urinary proteinsin group I than in group II but this was statistically insignificant. RegardingTNF-α, there was tendency towards lower urinary TNF-α level in group I thanin group II but it was statistically insignificant. Also there was tendency towardslower serum TNF-α in group I than in group II but this also was statisticallyinsignificant.