The mapping correlation between the displacements in the geometric center of gear and the displacement disturbance of every meshing gear pair is established based on geometric coupled model and stiffness properties of gear system. The distances between the center of gear and pinions, the meshing angular and the off-set angular of the center directions were discussed considering the lateral-torsional coupling loads. The mathematic description of additional meshing force caused by these factors was given.The load-sharing behavior was discussed for shield machine actuated by multiple pinions in which the lateraltorsional load and mounted locations of pinions are taken into account. The results show that the additional meshing force is dependent on the mounting locations of pinions. The variation of disturbance force’s direction leads to unsynchronized sinusoidal oscillation of pressure angle and extra meshing force near their original values. The total additional force changes with the layout of pinions.The reasonable design of the locations of pinions may decrease the failure accidents resulted in by the non-uniformed load transmission of multiple pinions.