This study will verify the direct effect of strategic application of information systems (IS) on firm performance of international freight forwarders through ascertaining three research objectives: the analyses of a causal link between IS and firm performance, an interaction effect between internal and external IS on firm performance, and gaps in firm performance among the stages of strategic application of IS. The data was collected from international freight forwarders. To achieve the objectives of this study, various analytical methods were used. The results of exploratory and confirmatory factor analyses are the basis of reliability and validity on the collected data. The results of structural equation modeling (SEM), moderated regression analysis (MRA), cluster analysis, analysis of variance (ANOVA) and post hoc analysis are the basis of testing the hypotheses. The results are as follows. First, strategic application of IS has a positive effect on firm performance. This means that international freight forwarders improve performance through strategic application of IS. Second, there is the interaction effect between internal and external IS on financial performance. This means that strategic application of internal and external IS is connected with financial performance. For this reason, there is a gap between IS investment and financial performance in the industry. However, the interaction has no effect on customer satisfaction. The reason is explained as passing over organizational and cultural factors which have an effect on the relationship between firms. Third, there are gaps in firm performance among the stages of strategic application of IS. The result shows that the stage of supply chain IS achieve the highest firm performance. The results mean that strategic application of IS has a direct influence on firm performance.