In this paper, a new method is proposed to chaotify a class of unknown discrete-time dynamical systems. First of all, the discrete-time fuzzy hyperbolic models (DFHMs) are employed to represent the discrete-time dynamical systems approximately. Then, a nonlinear state feedback controller is designed to chaotify the DFHMs. By revised Marotto theorem, it is proven that the chaos generated by this controller satisfies the Li-Yorke definition. An example is presented to demonstrate the effectiveness of the proposed approach.