The nuclear and Coulomb potentials between deformed nuclei with octupole deformations and arbitrary orientations are evaluated numerically. The effects of the octupole deformation on the potential between nuclei and the potential energy surface (PES) used in the description of the production of super-heavy nuclei (SHN) by heavy-ion fusion reactions are investigated in the di-nuclear system model. It is found that the nuclear octupole deformation significantly changes the shape of the PES, which may influence the fusion probability of the SHN. Also, PESs in the tip-belly and belly-belly cases are investigated. Finally, the quasi-fission barriers in the tip-tip and belly-belly cases are evaluated. It is found that the quasi-fission barriers of the belly-belly case are generally larger than those of the tip-tip case.