Abstract: This paper proposes an algorithm based on triangle coordinate system to solve the interpolation problem occurred in image nonlinear topological deformation process.First, mark original pixels according to their positional properties in an image, and then update those marks during the deformation process.Once the blank points generate, calculate the interpolation weights in a small neighborhood using integral image.If the weight is larger than the threshold, the corresponding point was needed and the cubic convolution interpolation was applied to it eventually.Experiments on expressional design and facial transition using multi-triangle grid demonstrate that this algorithm can solve the interpolation problem of topological deformation in the frame of triangle coordinate system effectively and improve the visual looks obviously.