Carbon nanotubes (CNTs) and other nanoparticles such as silicon carbide (SiC), alumina (AL 2 O 3 ) are used to improve the material properties of polymers and in general are considered to be highly potential fillers. However, questions concerning the proper type and amount of CNTs, e. g., single-wall CNTs (SWCNT), double-wall CNTs (DWCNT), or multi-wall CNTs (MWCNT) and other nanoparticles such as silicon carbide, alumina and their influence are still to be answered. This work studies the effect of the amount and types of nanofillers on the mechanical properties of epoxy based nanomaterials and their functionalization. In the present work, epoxy resin was modified with different types of nanofillers including SWCNT, DWCNT, MWCNT, SiC and AL 2 O 3 . The amount of CNTs (SWCNT, DWCNT and MWCNT) used for each type of CNTs were 0.1, 0.3 and 0.5 wt.-%. By contrast, the amount used for (SiC), and (Al 2 O 3 ) measured 0.5, 1 and 1.5 wt.-% for each type. Tensile test were conducted for each group to investigate the mechanical properties of epoxy based nanomaterials. The results show that CNTs of 0.3 wt.-% is optimal compared with other amounts, e. g. 0.1 and 0.5 wt.-%. The tensile strength at 0.3 wt.-% SWCNT/E, DWCNT/E and MWCNT/E increased by 44 %, 37.4 % and 35.9 %, respectively compared to the neat epoxy. For (SiC), and (Al 2 O 3 ), the results show that an amount of 1.5 wt.-% is optimal compared with other amounts, e. g. 0.5 and 1 wt.-%. The tensile strength at 1.5 wt.-% for Sic/epoxy and Al 2 O 3 /epoxy nanocomposite increased by 25 %, and 43 %, respectively compared to the neat epoxy. Finally, the results show that the (SWCNT) is optimal compared to the other nanofillers.