In photoisomerization polymer, the perpendicular optical control of the optical spatial soliton interaction is simulated by numerical method. Under control, the properties of two interacting solitons are damaged, the signal beam can give birth to phenomena such as the two beams to join together, or to detach and so on. We also give a physical explanation of the phenomena, that they are determined by the difference in the initiatial phases of the beams, the incident position of control-beam and so on. The effect of perpendicular optical control of interaction solitons can be applied to optical interlinkage, optical waveguide and so on.