Abstract: To determine a more accurate path of deformation between "homologous" images, this paper proposes a kind of method of image description based on triangular coordinate system, and verifies the deformation continuity of face images based on the proposed method. Firstly, the definition of the triangular coordinate system and the description method of the triangular texture features are presented. The triangular texture features remains unchanged when the structure of the image varies. Thus the determination of image deformation path can be simplified. Secondly, by mapping the triangular coordinates onto the Cartesian coordinate system the intermediate interpolation images are generated. Finally, in the improved bionic pattern recognition, a more suitable kernel path for face image transform is found, which enhances the effective coverage of the bionic neural network. The experimental results verify the validity of the promoted bionic pattern recognition.