Plant biofortified with iodine may be an alternative source of this element in human diet. The purpose of the research was to determine the effect of fertilization on quality of green plant biological iodine. Iodine in the form of KIO3 or KI was applied to the soil or sprayed on the plants. Iodine application (2.50 or 5 kg ha-1) was split, with the first half applied together with spring nitrogen fertilization and the other half applied one month before sampling for laboratory tests. In all the tested combinations of fertilization iodine increases iodine content in green plants compared to control. The application rates and means of fertilization with iodine salts did not adversely affect the biological quality of the plants.