A new approach to determine an optimum tire contour was developed and was applied to improve various tire performances following the corresponding objective function and constraints. Although several tire contour theories have been proposed in the past, some of them were based on a simple model and could not be used to improve tire performances effectively. On the other hand, others were not described by an equation and their application was limited. In the new approach, the optimization technology was applied to efficiently obtain the optimum contour by minimizing an objective function, while satisfying the constraints. The new approach was verified to be able to improve various tire performances.