Relationship between concentration of Mg and Cu in serum and the arterial wall was studied in patients with atherosclerosis obliterans (AO), aortic aneurysm (AA) and in the control group. The effect of ageing was also evaluated. The results showed increased serum concentration of Cu in the eldest control group (50-59 years) when compared to the younger (20-29 years). Serum concentration of Mg was decreased in AO and AA, and that in the arterial wall was lower in AA, than in controls. Concentration of Cu in serum and the arterial wall was higher in AO than in controls. Lower limb ischaemia results in decreased serum Mg and increased Cu in the critical degree as compared with the moderate degree of ischaemia. The ratio Mg/Cu was found lower both in serum and the arterial wall in AO and AA, as a result of ageing and vascular disease, and it could be better marker of ischaemia than individual element concentrations.