Nowadays, most apparel manufacturers try to adopt their production into a flexible manufacturing system to be able to meet low but Multifarious demands of their customers. In these systems, models are classified according to their properties and processed in sewing cells appropriate for their properties. However, there are always some differences within similar models, and therefore some modifications known as setup processes must be done when models are changed in the same sewing cell. Since setup process is not a value added factor for the cost of end products, they need to be kept at a minimum level. In this paper, optimization Of Setup times was studied by scheduling the entrance sequence of various models in all order group planned to be manufactured in the same sewing cell. The problem defined here corresponds mathematically to the "open path" Traveling Salesman Problem (TSP) with a definite starting point. It is classified as NP-complete.