A method to reduce vibration in a helicopter blade under a variable harmonic pressure loading using piezoelectric actuators is presented. The model of a helicopter blade is an equivalent aluminum plate. To decrease the amplitude in the resonant frequency range, piezoelectric actuators are set on the top of the plate. The results were obtained by using the ANSYS finite element code. The temperature analogy method instead of a variable pressure load is assumed for numerical analysis. The influence of piezoelectric actuators on the plate is considered. It is shown that the use of piezoelectric actuators to decrease the vibration of the plate is highly efficient. The most rational arrangements of piezoelectric actuators and the required amount of electric voltage are determined.