The aim of our work is to attempt to explain the relationships between knowledge-based resources, market orientation, learning orientation and innovation performance. Data were collected through a survey of 135 Tunisian companies operating in a variety of industries across the country. We used a principal component analysis for each concept and then performed a hierarchical regression analysis to achieve our objective. Our empirical study was able to provide assertions about the existing relationship between these variables. The results indicate that knowledge-based resources, learning orientation and market orientation have a significant effect on innovation performance. However, knowledge-based resources mediated the relationship between learning orientation and innovation performance in the Tunisian case.