To avoid iodine toxicity in crops and to make iodine-biofortified crops, it is important to study iodine uptake and metabolism in plant depending on its chemical forms. Using ion chromatography and inductively coupled plasma-mass spectrometry system (IC-ICP-MS) for the determination of form of iodine, plant uptake and metabolism of inorganic iodine and the behavior in the rhizosphere were studied. Iodide was detected in plant body, xylem sap and culture media of Iodate treated plants. Iodate would be reduced to Iodide by roots or in the rhizoshere readily, and rice plants would absorb the reduced Iodide. Higher plants would have the ability to reduce iodate to iodide.