This paper propounds addressing the design of a high gain observer optimization method in order to ensure a reliable state synchronization of nonlinear perturbed chaotic systems. The salient feature of the developed approach lies in the optimization of the high gain observer by using the optimal control theory associated with a proposed numerical algorithm. Thereby, an innovative quadratic optimization criterion is proposed to calculate the required optimal value of the observer setting parameter *θ*, characterizing the observation gain and corresponding to the minimal value of the cost function, by achieving a compromise between the correction term of the state observer and its observation error. Moreover, the exponential stability of the high gain observer is demonstrated within the Lyapunov framework. The efficacy of the designed approach is highlighted by numerical simulation on two prominent examples of nonlinear perturbed chaotic systems.