Exploring the factors that shape a start-up’s success has been the focus of a growing number of studies. Entrepreneurial teams have a high impact on new ventures' success. They significantly influence the growth, profitability, and innovation of new businesses, specifically in information technology (IT) start-ups. lot of new businesses are launched by entrepreneurial teams. However, there is limited knowledge about the impact of personal characteristics of entrepreneurial team members and their social interactions on the success of their business. This paper explores the effect of entrepreneurial team characteristics and their social interactions on the success of IT start-ups in Iran. The study employed a quantitative research design and data from 213 entrepreneurial teams in IT start-ups. The findings showed that heterogeneity, experience, self-efficacy, commitment, trust, and social interactions of entrepreneurial team members have a significant positive influence on the success of IT start-ups. Implications of the findings for policy, practice, and research development are discussed.