The Student Affairs professionals in the U.S. have had a special graduate preparation program since early twentieth century and expanded them in 1960s. The author believes that we can understand the nature of professionals of Student Affairs through the history of the standardization of preparation program. The purposes of this article are the following : to discribe how the character of preparation education was developed before the expansion in 1960s when the standards became a very important issue, to discuss how two different groups had a different view of preparation, and to examine what student affairs staff developed through the effort at standardization of preparation program.