Based on the statistical data on the practical ore-prospecting effect of geo-chemical methods employed by bureaus of geology and mineral resources ofvarious provinces or autonomous regions under MGMR, the present paper makesa comparison and illustrates the variation of ore-searching effects of geochemi-cal techniques in three different periods, i. e., from 1960 to 1975, from 1976 to1980, and from 1981 to 1985. It also analyses and discusses tbe reason for ob-taining such good ore-prospecting results.