Natural rubber (NR) containing fullerenol, C60-OH, was prepared by two methods; one by mixing C60-OH aqueous solution to NR latex followed by coagulation (wet method) and the other by mixing C60-OH powder with solid rubber by an open roll mixer (dry method). C60-OH mixed by wet method was homogeneously dispersed in the rubber, while one mixed by dry method was particles in the size up to 70 mu m. The former exhibited large reinforcing and antiaging effect than the latter. The large antiaging effect was explained by the finding that C60-OH had large radical scavenging ability and gel forming ability during heat treatment. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 3625-3631, 2010