The study was aimed at investigating the predispositions of the patients chronically treated with hemodialysis to nose and skin colonization with potentially pathogenic bacteria. The study involved 41 patients chronically hemodialysed and patients treated at the Department of Renal diseases or out-patient clinic (30 individuals). Smears from the nose and throat were taken from all patients and used for bacteriologic tests. In case of hemodialysed patients material for bacteriologic tests was additionally taken from the skin at the site of arterio-venous fistula and groin. It was found, that patients chronically treated with hemodialyses are more frequently colonized with enteric bacilli and coagulase-positive staphylococci that both hospitalized patients and those treated in out-patient clinic. No relationship between the presence of coagulase-positive staphylococci in the nose and throat and on the skin was seen despite such suggestions of other authors.