This paper presents an algorithm for fingerprint image restoration using a Digital Reaction-Diffusion System (DRDS). The DRDS is a model of a discrete-time discrete-space nonlinear reactiondiffusion dynamical system, which is useful for generating biological textures, patterns and structures. This paper focuses on design and evaluation of a special DRDS having a capability of restoring incomplete fingerprint images. The phase-only image matching technique is employed to evaluate the similarity between the original fingerprint images and the restored images. The proposed algorithm is useful for person identification applications using fingerprint images.