Hyperglisemia, increased angiotensin II ATİ reseptör activity, oksidative stress, decreasing intracellular A TP play an important rol in occurance diabetic nephropathy (DN). In our study, effects of angiotensin converting enzyme inhibitor (AÇEi) as enalapril (EN), and L-Carnitine (LC) were investigated on DN in streptozotocin-induced diabetic rats. Except healthy, patient control (HK, PK) groups, 2.5 mg/kg/day EN and 100 mg/kg/day LC were given in a water for six weeks. After 24 hrs urine collection, blood withdrowned by cardiac punction then, rats were sucrified. Erythrocytes count (Er), hemoglobin (Hb), hematocrit (Hct) in blood; and glucose, HbA 1c, urea, creatinine (pCr), uric acid (UA), P04, Cα2 ", Nα', K', albumin (Alb) in plasma; superokside dismutase enzyme (SOD) as an antioxidant, malonyl dialdehyte (MDA) as lipidperoxidation product (ROS) were measured in eryhtrocyte were measured. Daily excretion of urinary glucose (UG), albumin (UAE), N-acetyl-b-Dglucosaminidase (NAG) were measured, immunuhistochemical kollagene type IV accumulation and renal histopathology were investigated on light microscopy. After STZ injection DN was established with increased glucose, HbAlc, UG, UAE, NAG (P<000), urea, pKr (P<005). According to PK group, lower UG (P<.000), NAG, urine volume, PO4, and higher Alb (P<.05) in EN group, higher Er, Hb, lower urine volume, UG, NAG (P<.05) in LC groups were found. According to HK, nonsignificant increased MDA in PK, unchanged in EN and LC groups were found. Tubulo-glomerular basal membrane thickness and accumulation tip IV /collagen as DN findings significant in PK, moderate EN, and mild degree in LC group were found. Our findings suggests that, LC have protective effect on diabetic nephropathy like ACEi.