A wavelet transform is efficient for multiresolution signal analysis. Difference-of-Gaussian (DOG) wavelets belong to a particular class of wavelets that extract the information of a specific frequency range in an image. Different DOG wavelets are produced by simple diffusion and subtraction processes by using diffusion network. We propose an optoelectronic DOG wavelet transform system using the point spread function of the combined system, which is similar to the Gaussian function. The experimental results show that the proposed system has potential applications to the systems that require DOG wavelet transforms in real time. © 1997 Society of Photo-Optical Instrumentation Engineers.