Abstarct: With the development of the theory of structural safety in recent years , many Organizations Author Codes, LRFD method has been the basis of his work.This method is a design approach baxsed on probabilistic concepts that leads to a structural design safer and yet more economical than other methods Last updated at Iran Steel Codes, LRFD method as the basis for the design. Despite the many changes that have taken place in the 1392 edition, as well as load and resistance factor largely selected as America's steel Codes. Philosophy of the LRFD method to determine the partial safety factors baxsed on the principles of probability and statistics and a number of factors such as economic conditions, social and other conditions affecting the construction, such as the statistical properties of the steel used, and so on. So given the above conditions the Iran is different from the United States, may use the partial safety factors of AISC is not the expected result. In this thesis, due to climatic conditions and the statistical properties of existing materials in Iran and accurate methods of reliability, Level of safety of members designed by Iranian steel Codes is determined. Moreover, using the optimal GA, increased load factors and reduced the capacity of Iranian steel Codes governing the probability proportional to the structural steel will determine the safest and most economical way to achieve the design. Finally, sensitivity analysis of the statistical parameters, the degree of influence of these parameters on the level of safety members and performance regulations is checked.