The present study's main purpose is to determine the current-voltage (I-V) performance of Graphene (Gr) based hetero nanostructure produced on Al2O3/p-Si. Graphene synthesis was carried out using the chemical vapor deposition (CVD) technique on Copper (Cu) foils used as a metal catalyst and transferred onto Al2O3/p-Si using the conventional transfer method. The I-V characteristics of this structure were measured in the dark environment, and the electrical properties of the Gr/Si structure were characterized at room temperature. The rectifying ratio (RR) of the structure was found to be about 103 at +/- 3 V. The electrical properties of ideality factor (n), series resistance (R-S), and barrier height (Phi(b)) were examined by using the theory of Thermionic Emission (TE), Norde's method, and Cheung's method. The values of Phi(b), which were calculated using Norde's method, Cheung's method, and the theory of thermionic emission (TE), were found to be 0.69 eV, 0.71 eV, and 0.68 eV, respectively. The ideality factor was found to be approximately 3.89 according to the theory of TE. The values of series resistance were also determined using the Norde's method and Cheung's two different parameters (dV/dln (I) and H(I)) found to be 9.60 k Omega, 9.12 k Omega, and 5.94 k Omega, respectively.