CNT(3,3) and Al2O3 are two different materials that have excellent electrical and mechanical properties, and thus many research works have been done around these two materials for different engineering applications. Therefore, this research is conjected at modelling nanomaterial of Al2O3-CaO-CNT(3,3) layer by layer. The electrical and mechanical properties of the nanomaterial were simulated through density functional theory (DFT). The calculations were done based on the generalized-gradient approximation (GGA) of an all-electron (AE) method called the Perdew, Burke, and Ernzerh (PBE) of exchange-correlation functional. The nanomaterial demonstrates an excellent energy gap (EG) of 0.007 eV and 0.000 eV (approximately equal to that of conductors) for upward and downward spin, respectively, lower than the energy gap of Al2O3, which is mostly used as an insulator in microelectronics. The energy gap (EG) majorly decreases with increasing temperature following models with regression values close to 1, which is useful for applications in microelectronics, fuel cells, and batteries. The nanomaterial also demonstrates a good mechanical strength as the anisotropic Young's modulus is 20.234 GPa like the one reported for CNTs, and a better shear modulus of 9.412 GPa than that multi-wall CNT, although lesser than the Young's and shear modulus of Al2O3. The nanomaterial was predicted to be mechanically stable.