C60 fullerene and its derivatives have been used in a number of consumer products and their potential applications in biomedical and environmental engineering are being actively pursued. Existing toxicity data indicate that industrial-scale production of C60 fullerene poses a potential threat to the environment. Understanding the fate and transport of C60 in the environment is necessary to evaluate its environmental impact. Although natural organic matter (NOM) is known to stabilize colloids, its influence on C60 behavior in aqueous phase has not been studied. Our study aims to determine the effect of aquatic NOM on the formation and physicochemical properties of aqueous C60 suspension, also referred to as n-C60 due to the aggregate nature of the particles formed. The effects of two major NOM components, humic acid (HA) and fulvic acid (FA), were investigated using n-C60 samples prepared by two methods: emulsification of C60 solution in toluene with water followed by sonicating volatilization of toluene, and directly mixing C60 dry powder with water. Dynamic light scattering (DLS), atomic force microscopy (AFM), and transmission electron microscopy (TEM) were employed to analyze particle size and morphology. Particle surface zeta potential was determined by electrophoretic mobility measurement using phase analysis light scattering. NOM was found to induce disaggregation of preformed n-C60 particles. Moreover, directly mixing C60 dry powder with water containing NOM formed stable n-C60 suspensions with particle sizes of 2-4 nm. These results indicate that NOM may play a critical role in transport and toxicity of C60.