One of the most important and dangerous environmental pollutants is the presence of heavy metal ions in industrial units effluent. Among the heavy metals, mercury deriving from industrial wastewater discharges of chlor-alkali, paper and pulp, oil re?nery, paint, pharmaceutical and battery manufacturing has particular importance due to toxicity, bioaccumulation and environmental effects on living organisms. Various physical and chemical methods, including coagulation and sedimentation, reverse osmosis, chemical reduction, adsorption and ion exchange are used to remove mercury from wastewater and contaminated waters. In recent years, adsorption process has taken more attention due to high efficiency and approximately low cost. The necessity to reduce the amount of mercury ions in industrial wastewater stream, has led to an increasing interest to find selective adsorbent. Different adsorbents are used for removal of mercury from industrial wastewater. But considerable attention has been devoted to use nano-adsorbent such as nanoparticle and nanostructure in removing metal contaminants from industrial wastewater because of their high specific surface, high area to volume ratio and consequently the high efficiency. In this study, two carbon nanostructures, MWNT-COOH and CNFs, were applied for mercury adsorption from synthetic solutions and industrial wastewater using batch and column techniques. The parameters affecting the sorption including equilibrium time, pH, initial mercury concentration, adsorbent amount, the effect of disturbing cations and ionic strength were investigated. Some physical, chemical and morphological properties of adsorbents were determined by Brunauer Emmett Teller (BET), X-ray diffraction, fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Adsorption kinetics studies showed that the adsorption of mercury by MWNT-COOH and CNFs is rapid. The kinetic data for mercury sorption by CNFs were precisely described by Pseudo-First order and pseudo-second order models. The optimum pH for mercury sorption by MWNT-COOH was between 3/0-7/0 and by CNFs between 4/0-7/0. The suitability of the Langmuir, Freundlich and Redlich-Peterson adsorption models to the equilibrium data was investigated for mercury-sorbent system. Mercury adsorbed on MWNT-COOH was fitted well to Redlich-Peterson model and on CNFs to Redlich-Peterson and Freundlich model. Maximum capacity of mercury adsorption was 500 mg/g for both adsorbents. The presence of metal cations including cadmium, chromium, copper, nickel, lead , and zinc with two concentrations (50 and 100 mg/L) did not affect significantly the mercury Key words Mercury, Adsorption, MWNT-COOH, CNFs, Adsorption kinetic, Adsorption isotherms.