Entrepreneurship of a founder and psychological characteristics are very important factors for the start-up success. To understand the importance like this, this study investigated effect relationships of the entrepreneurship and psychological characteristics on the start-up success. For this, 122 copies of the questionnaire were empirically analyzed for the youth entrepreneurs who entered the youth founder academy which is founded and managed by the Small and Medium Business Corporation. According to results of analysis, both the entrepreneurship consisting of proactivenss, risk taking and autonomy, and the internal locus of control, the psychological characteristics were found to have positive effects on the start-up success. Therefore, this study suggested theoretical and practical implications, as below, according to the results. Firstly, we must be aware of the importance of the entrepreneurship from the perspective of a successful establishment, and, prospective entrepreneurs, who are planning to the start-up, have to judge their entrepreneurship and, only then, make a decision. Secondly, we have to put our best efforts into developing more effective education on start-up, which deals with improving youth founder's entrepreneurship. Therefore, education institutions for start-up are needed in order to develop educational programs such as "Entrepreneurship Training Programs". Thirdly, we must recognize that the role of family is important because most entrepreneurship and psychological characteristics are formed in a person's childhood. Forth, the entrepreneur, themselves, must realize that they has to make an effort to improve their entrepreneurship. Lastly, youth founder's internal locus of control has to be enhanced. Thus, greater attention is required from both the entrepreneur themselves, and educational institutions for start-up.
