The objective of this research was to investigate the possibility of a novel electrode-area-weighted (EAW) method of implementing wavelet transform processor (WTP) with surface acoustic wave (SAW) device. The motivation for this work was prompted by a diffraction problem of the WTP using SAW device. In this paper, we propose a novel EAW method in order to solve the diffraction problem. When the electrode areas of the EAW wavelet interdigital transducer (IDT) (i.e. the input IDT) are designed according to the envelope areas of the wavelet function, the impulse-response function of the EAW wavelet IDT is equal to the wavelet function, so that the novel EAW WTP using SAW device can be fabricated. In this study, we also present the diffraction problem, the substrate material, and the electrode number of the output IDT as three key problems, and the solutions to the three key problems are implemented.