Fullerene is one of the forms of carbon nanoparticles. Analysis of the literature data shows that the effects of fullerenes and their derivatives on plants are very contradictory (Zaytseva O. and Neumann G., 2016). It had been shown that C60-fullerene reduced the growth of biomass of corn and soybean seedlings. On the other hand, it was found that polyhydroxylated fullerene stimulated seed germination, accumulation of biomass and metabolites in the tissues of the tropical liana Momordica charantia. Moreover, fullerenes can reduce the effects of some dangerous toxins and absorb antibiotics and organic pollutants (Zaytseva O. and Neumann G., 2016). It had been also shown high adsorption of lead and copper (III) by carbon nanomaterials (Zaytseva O. and Neumann G., 2016). Significant advantages of carbon nanoparticles as sorbents are provided by large surface area, mechanical and thermal stability and potential antibacterial properties. This application of nanoparticles appears to be extremely important in sustainable agriculture and the need to prevent environmental pollution. Nanotechnology based on carbon nanomaterials could improve strategies for eliminating pollutants or reducing their bioavailability. Additional sorbing properties can be provided by the functionalization of carbon nanoparticles with chitosan. Chitosan is a universal sorbent capable of binding a wide range of organic and inorganic substances. Chitosan also demonstrates antibacterial, antifungal and antiviral properties. The purpose of this work was to obtain a fullerene-chitosan complex and to study effects of fullerene and fullerene-chitosan on the growth of barley seedlings. Another purpose was to study the modification of physiological processes of barley seedlings by fullerene and fullerene-chitosan in presence of cadmium salts. Cadmium is the one of the most widespread and dangerous heavy metals. It is well known that the accumulation of potentially toxic heavy metals in soil and water has become a global environmental threat. The increased content of heavy metals can pose huge risks to ecosystems and human health. Fullerene and fullerene-chitosan complex (10-500 mg/L) were used in this work. A fullerene-chitosan complex was synthesized in the Institute of bioorganic chemistry of the National Academy of Sciences of Belarus. The effects of fullerene and fullerene-chitosan on physiological parameters of barley seedling were measured. Dry weight, relative water content, content of chlorophyll, flavonols, and nitrogen balance index (NBI) of 5-14 day old seedlings were evaluated. It was found that fullerene and fullerene-chitosan did not significantly affect on physiological parameters in control conditions. At the same time, both fullerene and fullerene-chitosan stimulated the accumulation of dry mass, chlorophyll content and NBI in plants grown in presence of cadmium. The fullerene-chitosan complex was especially effective under cadmium stress: the studied parameters increased by 40%, i.e. almost to the level of control. It was also noted that fullerene and fullerene-chitosan increased peroxidase activity in the leaves of seedlings in control and reduced this parameter under cadmium stress. The fullerene-chitosan complex also demonstrated peroxidase-like catalytic activity higher than those of fullerene. Thus the observed effects most likely indicate the sorption of cadmium ions by fullerene and, especially, fullerene-chitosan and possible peroxidase-like catalytic activity of fullerenechitosan. Moreover the obtained data allow us to conclude that the modification of the physiological and biochemical processes in the aerial part of seedlings during cadmium tolerance responses by fullerene and fullerene-chitosan is accompanied by a change in the ROS metabolism.