Abstract: The placement of piezoelectric actuators was studied in a piezoelectric de-icing system with a plane plate as research target for the purpose of engineering applications of piezoelectric variation de-icing method. Cross sections in the length direction were the testing objective. The modal vibration mode of the two-dimension piezoelectric coupling model was studied using the finite element analysis methods. The third order vibration mode was chosen as optimal mode of the de-icing mode in the length direction, and this vibration mode was treated as basic mode in the following research. The elastic strain and the displacement at the interface between ice and plate were employed as the representations of the excitation, and the arrangement of the piezoelectric actuators in the width direction was simulated and analysed using the three-dimensional finite element model with three different arrangement aspects:the number of the piezoelectric actuators, the relative patch number of the actuators and the relative patch concentration of the actuators. The results show that a better incentive effect is secured on the structure with the actuators place at middle position and edge position in the width direction of The actuators are needed to be placed to avoid a small elastic strain in the width direction. When the actuators are placed at the edge position of the plate, a good incentive effect can be gained on the targeted icing area of the plate. In the same contact area, the excitation of the plate can be improved by reducing relative number of the piezoelectric actuators or improving the concentration of the actuators. Large scale piezoelectric actuators are better choices when patch area and attached requirement are available. For practical engineering research of the piezoelectric de-icing system, a feasible design can be provided by flexible adopting placement regulations of piezoelectric actuators.