The sorption potency of any material toward different radionuclides is closely related to porous structures and the surface functional groups. In this research, for the first-time, we report the process conditions to attain a new low cost carbonaceous adsorbent from mint waste (CAMW) containing both micro- and meso-pores. The new sorbent was analyzed using various analytical techniques. From the study of surface properties it was found that synthesized material possesses a high surface-area (BET) of 735.75 m2 /g, Langmuir surface-area of 1015.0 m2 /g, total pore-volume of 0.596 cm3/g and average pore-diameter of 0.60 nm with a reasonable yield, 32.4%. Radionuclides contamination in aquatic environment has become a dangerous threat today. Removal and recovery of these species (anionic and cationic radionuclides) prior to extrusion into the environment is essential for the safety of organisms. Therefore, we evaluated removal efficiencies of this new carbonaceous material as a dual-function sorbent for the retention of cations (Cs(I), Co(II), Sr(II) and Eu(III)) and anions (Cr(VI) and Mo(VI)) from aqueous solutions. Sorptive removal of various radionuclides (cationic and anionic species) from environmental samples confirmed the validity of results gained in these studies. All these values indicate that prepared CAMW possesses excellent adsorption capacity for both cationic and anionic radionuclides and can generally be considered as an advanced adsorbent.