The cultivation of energy crops such as Miscanthus × giganteus offers dual benefits for Ukraine’s bioeconomy – sustainable biomass production and environmental restoration. This study evaluates the phytoremediation potential of the Miscanthus × giganteus cultivar Athena by analyzing the accumulation intensity of selected heavy metals (Pb, Cd) and trace elements (Zn, Cu) in its aboveground biomass grown on grey forest, chernozem, and sod-podzolic soils. Field and laboratory assessments revealed that the accumulation efficiency varied considerably with soil type. The highest uptake of copper (Cu) was observed on sod-podzolic soils, while zinc (Zn) peaked on grey forest soils. In contrast, lead (Pb) showed maximum accumulation on chernozem soils. Despite these differences, the hazard ratio (HR) for all studied elements remained below the critical threshold (≤1.0), confirming the environmental safety of the harvested biomass. These findings emphasize the potential of Miscanthus × giganteus not only as a renewable resource but also as an effective phytoremediation agent for heavy-metal-contaminated agroecosystems.