Hyperaccumulator biomass harvested after heavy-metal phytoremediation must be considered as hazardous waste that should be contained or treated appropriately before disposal or reuse.As a potential method to detoxify the biomass and to convert this material to a suitable bio-energy resource,the hydrothermal upgrading process was applied to remove heavy metals and upgrading crude bio-oil from Phytolacca americana L.stems and leaves harvest.