Abstract: Various enzymes, in particular Cu,Zn-superoxide dismutase (SOD), catalase and carbonic acid anhydrase, are recovered from blood by admixing wholly or partly isolated blood cells with ethanol or a homologous alcohol until a concentration of 10 to 70% by volume and allowing them to stand for hemolysis of the blood cells and denaturation of the hemoglobin, and then adding water up to the double volume or more, and removing the precipitate of cell residuals, hemoglobin and other denatured proteins from the suspension. Then the desired enzymes are isolated from the solution obtained.In particular, SOD and catalase can both be isolated by chromatography of the solution at a pH of 4.7 to 5.5 on a cation exchange resin of the same polarity as SOD in the pH range used and elution of the resin with a buffer solution which has a pH in the range 4.7 to 7.5 and an ionic strength in the range 0.01 to 1.0 M, SOD being eluted at the lowest pH and/or the lowest ionic strength.