Minimizing brake squeal is one of the most important issues in the development of high performance braking systems. Recent advances in numerical analysis, such as finite element analysis, have enabled sophisticated analysis of brake squeal phenomena, but current design methods based on such numerical analyses still fall short in terms of providing concrete performance measures for minimizing brake squeal in high performance design drafts at the conceptual design phase. This paper proposes an optimal design method for disc brake systems that specifically aims to reduce brake squeal by appropriately modifying the shapes of the brake system components. First, the relationships between the occurrence of brake squeal and the geometry and characteristics of various components is clarified, using a simplified analysis model. Next, a new design performance measure is proposed for evaluating brake squeal performance and an optimization problem is then formulated using this performance measure as an objective function. The optimization problem is solved using Genetic Algorithms. Finally, a design example is presented to examine the features of the optimal solutions and confirm that the proposed method can yield useful design information for the development of high performance braking systems that minimize brake squeal.