Urinary excretion of cadmium was examined for 133 students of Kaneda Junior High School along the River Sasu and Shiine basin, Tsushima Island, and 33 students of a Junior High School in Nagasaki City. 1) By classifying the urinary Cd concentrations according to residential areas of students, the differences among areas were found, and students living in A, F, or E area in Tsushima excreted more Cd than those in other places. 2) The students whose family occupation is a farmer excreted more Cd than those of non-farmers. 3) No difference was found, in Zn excretion and the higher the Cd concentration, the smaller the Zn/Cd ratio was. 4) No difference was found in urinary Ca and inorganic P in any area.