The ICP-OES method is used for heating and ionizing the reaction gas adopting the high temperature produced by high frequency induction,then determining the content of constant and trace elements adopting the characteristic spectral lines emitted by elements. Zinc iron calcium content in compound zinc iron calcium particles was determined by ICP-OES method which was after wet digestion samples, the content of zinc, iron, calcium was determined at the same time by ICP-OES method. The results show that the detection limit of the elements under test is 0.2 ~ 0.5μg/L, precision RSD is 0.65% ~ 1.92%, the recovery is 99.50%～102.50%. This method has the characteristics of fast, simple, high sensitivity, is a relatively ideal method for determining the content of constant and trace elements in drugs, food and health care products.