This paper delves into the study of the factors that influence the international competitive position of international new ventures, and consequently, their international performance. By combining international entrepreneurship and marketing disciplines, this work attempts to emphasise the importance of relational knowledge by the influence of network market orientation on the international results obtained by these firms through the mediating effect of competitive advantages. The approach was used to test our hypotheses. The results obtained, using structural equations models and multi-sample analysis, confirm that network market orientation is a determining factor for new ventures to achieve superior international results. This influence is observed indirectly with the mediating effect on the differentiation- and cost-based competitive advantages developed by these firms. This study extends previous international entrepreneurship research, including insights from the marketing discipline on antecedents of international new ventures’ competitiveness and success in foreign markets. In addition, the results obtained encourage entrepreneurs in the international context to consider the explicit value of other factors different from experiential knowledge, which the company acquired gradually with increasing its experience in the foreign market, to realize the potential value of relational knowledge associated to network market orientation as an antecedent for the achievement of competitive advantages in the international market.