This paper proposes Poisson equation based image fusion algorithm for the implementation of uncomplicated completion and seamless splicing of digital image. This method constructs image reconstructed from the gradient map via the solving Poisson equation in the field of images needing to be completed and fused and uses MFC and MATLAB to process the simulation. This paper compares the examples and results of practical completion and fusion and discusses the real application effect. Experiment result shows that the image editing method based on Poisson equation can relatively better implement the uncomplicated completion of the image and the fusion between single background color images.