The serum lipoprotein was analyzed in 32 patients with chronic renal failure and 34 patients with hemodialysis, by the method of polyacrylamide gel electrophoresis. Patients with chronic renal failure and these with hemodialysis had moderate hypertriglyceridemia. In polyacrylamide gel electrophoresis, the abnormal broad midband lipoproteins between beta and pre-beta lipoprotein appeared in 11 patients with chronic renal failure and 30 patients with hemodialysis. In patients with chronic renal failure, the incidence of broad midband lipoproteins was increased in relation to the serum creatinine level. The alpha lipoprotein was decreased in 22 patients with chronic renal failure and 30 patients with hemodialysis. These results suggest the renal excretory function might have an important relationship with the accumulation of this abnormal lipoproteins in patients with chronic renal failure and hemodialysis.