We investigated the effects of carbon nanotube (CNT) functionalization with silanes and temperature on the tensile and fractural characteristics of CNT/epoxy nanocomposites. Three groups of nanocomposites were fabricated using unmodified, oxidized and silanized CNTs, each at 0.1 wt%. Tensile and fractural tests were performed using the three nanocomposite samples at -30 degrees C, 20 degrees C, and 45 degrees C. Results showed that the tensile strength of silanized samples at -30 degrees C was about 89% and 241% higher, respectively, than at 20 degrees C and 45 degrees C. The elastic modulus of silanized CNT nanocomposite at -30 degrees C was about 52% and 871% higher, respectively, than at 20 degrees C and 45 degrees C. The fracture toughness of silanized samples was higher than those of unmodified and oxidized samples at all temperatures. However, fracture toughness decreased with decreasing temperature. Specifically, fracture toughness of silanized nanocomposites at -30 degrees C was about 76% and 117% lower, respectively, than those at 20 degrees C and 45 degrees C.