The blended latex of natural rubber (NR) and styrene butadiene rubber (SBR) at dry weight ratio of 80/20 (NR/SBR) was reinforced with a very low loading level of either carbon nanotube (CNT) or nanosilica (nano-SiO2) (0.1-0.4 phr). The CNT and nano-SiO2 were compounded with NR/SBR rubber blend and other chemicals necessary for vulcanization in the latex state. The obtained nanocomposite latex was cast into thin sheet on a glass mold and then cured in an oven at 80°C for 3 h. The cured samples were subjected to the tensile, dynamic mechanical and thermal tests. The results revealed that the nanofillers have improved their tensile strength, modulus at 300% strain, dynamic mechanical properties and thermal stability but reduced the elongation at break. It was also observed that at similar nanofiller loadings the reinforcing effects of CNT are more noticeable than that of nano-SiO2.