Abstract: Objective To understand the change of blood zinc,copper,iron,calcium,and magne sium among heroin addicts one year after the methadone treatment.Methods The contents of zinc,copper,iron,calcium,and magnesium in the blood were determ ined with MP-2 stripping analyzer among 96 he roin addicts one year after the methadone treatment and 74 healthy controls.Results The contents of serum zinc,iron,calcium,magnesium,and copper were 7.02±2.02,14.12±3.77,59.47±19.60,35.07±6.23,and 2.67±2.43 g/L before the one year methadone treatment and those of after the treatment were 8.46±2.54,14.20±5.98,67.75±14.54,36.38±9.54,and 2.87±1.13 g/L for the hero in addicts and those of the controls were 7.65±2.05,15.02±3.71,95.44±20.38,36.19±8.83,and 3.03±1.80 g/L,respectively.After the methadone main tenance treamtent,the contents of blood zinc and calcium increased significantly (P < 0.01),whereas the contents of copper and magnesium showed noobvious change (P > 0.05) among the addicts.There was a significant decrease in blood concentration of calcium in the hero in addicts compared to that of the healthy controls (P < 0.05).There was no significant difference in blood concentrations of copper,magnesium,iron between hero in addicts and healthy person(P > 0.05).Conclusion The blood calcium and zinc content significantly increased in hero in addicts one year after methodone maintenance treatment.