The introduction deals with of the history, etiology and, briefly, clinical manifestations of endemic nephropathy. The authors state that a large number of investigations have been done until today, but without producing a diagnostic test for early diagnosis of the disease. This led the authors to pursue certain laboratory investigations. The control group consisted of 30 healthy individuals while patients diagnosed as Endemic Nephropathy were grouped according to stages of the disease: initial, developed, terminal stages. Nucleotides in erythrocytes (5' UMP, 5' IMP, 5' GMP, 5,CMP, 5' AMP, 5' ADP, 5' ATP) were determined on the Acidic Aminoanalyzer, with use of a special UV detector. Catecholamines in the urine were determined by using ratiofluorometery. Creatinine phosphocinase, hydroxybutirat--dehydrogenase and 2,3 DPG were determined on the "Carlbiochem" enzymometer. LDH, its isoenzymes as well as its profile were determined by electrophoresis on starch gel. Specific proteins such as haptoglobin, alpha 2 macroglobulin, alpha 1 antitrypsin, alpha 1 acid glycoprotein, properdin factor B, ceruloplasmin were determined on the Immunochemistry Analyzer. Total cholesterol and cholesterol in lipoproteins fractions VLDL, LDL and HDL were determined on the Cholesterol Analyzer. All results were evaluated statistically. Our conclusion is that they are interesting and contribute to the diagnosis of endemic nephropathy.