Abstract: In order to maintain an appropriate relationship between the planning layer and the control layer of autonomous underwater vehicle (AUV), with Itti visual attention model considered as a reference, a planning instruction understanding (PIU) model based on attention mechanism is presented, and the processes of PIU and the secondary planning are established. The attention focus of planning instruction is obtained using fuzzy reasoning for analyzing the feature and significance of instruction element. Furthermore, the secondary planning is implemented adopting attention focus, which can ensure a higher priority execution of the state concerned by the planning layer. The simulation results demonstrate that the proposed PIU process can not only realize the acquisition of the instruction intention of planning layer, and the planning instruction can be executed more effectively, but also the motion control effect is heightened and the intelligence level of control layer is improved.