Lactarius acerrimus macrofungus was evaluated as low-cost and influential biosorbent for bio-removal of Hg(II) from aqueous solution. The chemical structure and surface morphology of the macrofungus was characterized by using FT-IR and SEM/EDS techniques. The Freundlich and Langmuir isotherms were modeled to study the sorption behavior regarded with for bio-removal of mercury using the batch method. The Langmuir model was found to be the best fitted model. The maximum bio-removal capacity of the macrofungus was found to be 134.9 mg/g at pH 5. The batch experiments were also to investigate to point out different parameters having a vital the bio-removal of mercury. The kinetic studies indicated thatthe pseudo second order (PSO) model was best fitted to the experimental values. The thermodynamic parameters proved the spontaneous and exothermic nature of the bio-removal process. Furthermore, the cycling examinations demonstrated that the L. acerrimus macrofungus had reasonable reuse performance. Display omitted •L. acerrimus macrofungus as low-cost and novel sorbent was used effectively for bioremoval of Hg(II) from aqueous solution<.•The maximum bioremoval capacity of the macrofungus was found 134.9 mg g−1<.•The macrofungus had sufficiently high reusability performance <.•The bioremoval of Hg(II) using macrofungus was well fitted to the pseudo second order kinetic model<.•Thermodynamic calculations proved the spontaneous and exothermic nature of the bioremoval process<.