The aim is to study the migration of uranium-238 in the soil-plant system by the example of the culture of flower - marigold (Tagetes erecta). The experimental containers with soil were prepared. Seeds of plants were planted in the container four weeks from the start of the experiment. Oil, formation water, oil with salt uranium have been introduced in the container after two weeks. The soil with the plant roots were collected at the end of the experiment. One part of the soil was dried at 80 ⁰C, the other kept moist. Soil extracts were obtained by sequential fractionation. The plants were divided into above-ground and root parts and dried. Every part of the plant was subjected to ammonium acetate extract, and then samples were dissolved by “wet ashing”. The samples were tested by ICP-MS. The following conclusions were obtained. The maximum of the uranium (98%) associated with the components of the soil (organic matter, clay minerals) after application. In wet soils the mobility of uranium above. Oil and produced water increases the allocation of uranium, which resides in the soil earlier. The uranium content of the root and ground parts of the plants in the systems with the addition of oil and produced water is much higher than in the control system.