This study empirically analyzes how the career orientation factors of startup entrepreneurs affect entrepreneurial satisfaction as well as business sustainability. We propose directions for startup sustainability and development. Based on previous research, we defined the career orientation of entrepreneurs through the five orientation factors of security, autonomy, technical competence, managerial competence, and entrepreneurial creativity. We constructed a research model to determine whether these factors have a causal relationship with entrepreneurial satisfaction or business sustainability through the medium of organizational entrepreneurship. We surveyed startups in Korea using a questionnaire and collected and analyzed a total of 282 points of survey data. The analysis results demonstrated that the entrepreneurial creativity and managerial competence of the members of a startup can play an important role within entrepreneurial satisfaction and business sustainability. Both autonomy and technical competence exhibited no effect on entrepreneurial satisfaction and business sustainability through the medium of entrepreneurship, while security showed a negative effect. In order to improve entrepreneurial satisfaction and achieve business sustainability, we confirmed that it was more important for startups to consider the creativity and business management competences of entrepreneurs rather than pursue business security or have a technology-oriented attitude.