Concentrations of the total, dissolved and particulate iron in waters of Lake Eui-Am have been determined spectrophotometrically on August 14, 1970. O-phenanthroline was the reagent used. Iron contents of the lake water were varied by the station and depth. Analyses showed variations in the total iron ranging from 238 to 2,643 ${mu}$g/l (mean value 1,028${mu}$g/l); the dissolved iron varied from 34.5 to 137.7 ${mu}$g/l (mean value 83.0${mu}$g/l), and the particulate iron varied from 179 to 2,544 ${mu}$g/l (mean value 943 ${mu}$g/l). Three forms of iron tend to increase with depth. This is believed that the suspended matter plays an important role in regulating of iron contents in summer season.