Research findings suggest that networks offer small and medium-sized enterprises (SMEs) opportunities to internationalize successfully. However, the role of internal organizational competence in the process of developing and maintaining such networks in hostile external environments has received little attention. The aim of this study is to shed light on the relationship by examining the positive influence that the network competence of SMEs has on their propensity to internationalize, and on their subsequent international performance. Given that the willingness of firms to enter and perform well in markets appears to also depend on environmental hostilities, this external influence on SME internationalization is incorporated into the study. We also examine whether the level of environmental hostility moderates the relationship between network competence and SME internationalization. The empirical part of the study comprises a web survey of 298 Finnish SMEs representing five different industry sectors: metal, food, furniture, software, and knowledge-intensive business services. Confirmatory factor analysis and regression models are used in the analysis. The results indicate that higher levels of network competence are positively related to the propensity of SMEs to internationalize, as well as to their international performance. Conversely, the level of environmental hostility has a negative effect on the performance measure, but not on the internationalization propensity. Additionally, the influence of network competence is not moderated by environmental hostility. The results indicate that internal network competence and external environmental hostility play a role in SME internationalization, and that the positive influence of network competence exists independently of the hostility in the environment.