The effect of the Martian crustal magnetic field on ion escape is the focus of considerable interest. Directions of Martian magnetic field determined by the interaction between Mars’ crustal and interplanetary magnetic fields have been suggested to play a significant role on ion transport around Mars. In this study we investigate the physical mechanism deflecting O₂⁺ transport in two typical magnetic field orientations at horizontal plane by performing three-dimensional multi-fluid Hall magneto-hydrodynamic (MHD) simulations. Cross validation of tThe simulation results of cross validation byfrom considering the Martian G110 crustal field model and equivalent source dipole model reveals that due to the Hall electric force, O₂⁺ ions flow tends to be accelerated eastwards in the outward magnetic field region occupied by outward magnetic fields, and westwards in the region with inward one mainly by themagnetic fields Hall electric force. These results are helpful for understanding how the deflection of Martian atmospheric ions flow are influenced by the Martian magnetic field environment and the impact of the crustal fields on the motion of atmospheric ions in the Martian space environment.