This paper concerns the non-fragile guaranteed cost control for nonlinear first-order hyperbolic partial differential equations (PDEs), and the case of hyperbolic PDE systems with parameter uncertainties is also addressed. A Takagi-Sugeno (T-S) fuzzy hyperbolic PDE model is presented to exactly represent the nonlinear hyperbolic PDE system. Then, the state-feedback non-fragile controller distributed in space is designed by the parallel distributed compensation (PDC) method, and some sufficient conditions are derived in terms of spatial differential linear matrix inequalities (SDLMIs) such that the T-S fuzzy hyperbolic PDE system is asymptotically stable and the cost function keeps an upper bound. Moreover, for the nonlinear hyperbolic PDE system with parameter uncertainties, using the above-design approach, the robust nonfragile guaranteed cost control scheme is obtained. Furthermore, the finite-difference method is employed to solve the SDLMIs. Finally, a nonlinear hyperbolic PDE system is presented to illustrate the effectiveness and advantage of the developed design methodology.M. Chen et al. modes. This suggests one should start form the infinite-dimensional model itself to control the nonlinear hyperbolic PDE systems, and some control approaches have been reported, including the optimal control method [1,2], the sliding mode control method [10,20], the model predictive control method [19], the nonlinear control method through a combination of PDE theory and geometric control techniques [7] and the heuristic dynamic programming (HDP) method [31].Over the past few decades, there has been rapidly growing interest in fuzzy control of nonlinear systems. Particularly, since the so-called Takagi-Sugeno (T-S) fuzzy model [21] was proposed, as a popular and powerful tool in approximating a complex nonlinear system, it has been made a great of results [3,5,6,9,11,[22][23][24]. As a common belief, this fuzzy model-based control technique is conceptually simple and effective for controlling complex nonlinear systems modelled by ordinary differential equations. Recently, consider the infinite-dimensional nature, a T-S fuzzy-PDE-model-based control design was proposed for nonlinear hyperbolic PDE systems in [27]. A T-S fuzzy hyperbolic PDE model was presented to accurately represent the nonlinear hyperbolic PDE system, and the state-feedback controller distributed in space was designed by the PDC method such that the PDE system was exponential stable [27]. Based on the T-S fuzzy hyperbolic PDE model, the H ∞ control and guaranteed cost control of nonlinear hyperbolic PDE systems were also addressed in [25,32], respectively.To our best knowledge, there have been few results on the non-fragile control for nonlinear PDE systems. Non-fragile control is to design a feedback controller that will be insensitive to some error in gains of feedback control [17]. In practical applications, imprecision in controller implementation caused by finite word length in any digital systems or additional turning of parameters in the final ...