Purpose – The purpose of this paper is to examine innovation from a knowledge-based view by exploring the effect of knowledge processes and knowledge intensity on innovation performance. Design/methodology/approach – First, a theoretical model of the connections between knowledge processes, knowledge intensity and innovation performance is presented. The posited hypotheses are then tested statistically, using a survey dataset of 221 organizations. Findings – The result shows that while all knowledge processes have a beneficial impact on innovation, knowledge creation impacts innovation the most and fully mediates the impact of knowledge documentation, intra-organizational knowledge sharing and external knowledge acquisition on innovation performance. Furthermore, knowledge intensity increases all knowledge processes. Knowledge intensity also moderates the relationship of documentation and knowledge sharing with knowledge creation. The interaction effect is negative, meaning that firms in less knowledge-intensive conditions will benefit more from documentation and knowledge sharing for their knowledge creation purposes, and ultimately innovation. Research limitations – The data are limited to companies from Finland, Russia and China. Practical implications – To promote innovation, managers should pay close attention to knowledge creation processes in organizations. Furthermore, knowledge creation can be facilitated by ensuring efficient documentation procedures, and internal and external knowledge sharing and acquisition practices. Documentation and knowledge sharing are especially effective means to promote knowledge creation for non-knowledge intensive firms. Originality/value – This paper makes a contribution to the existing literature by building and testing a knowledge-based model of firm innovation and articulating the inter-relations of knowledge processes and knowledge intensity with innovation performance.