From the perspective of Resource Based View Theory companies pursue sustainable competitive advantages in their resources and capabilities, analyzing and strengthening them (Penrose, 1959; Wernerfelt, 1984; Barney 1991; Amit & Schoemaker, 1993; Peteraf, 1993). So strategy of the organization should focus on its core competencies because they allow maximize value of the organization (Prahalad & Hamel, 1990). Therefore knowledge has become one of the most important intangible assets for the company (Nonaka, 1994; Scarborough et al., 1999; Storey & Barnett, 2000; Lee & Sukoco, 2007; Carbonara & Caizza, 2008; Li et al., 2009) and in particular the process of creation of knowledge within the organization (Nonaka, 1994, Nonaka & Konno, 1998). Similarly, consideration of a reverse flow in logistics amplify the company's competitive capabilities in the sense of increasing resources and capabilities on which to develop the potential of the organization and to achieve, in this way, the desired competitive advantage sustainable, because to meet the increasing needs of customers demanding, the product must be not only quality but also highly competitive, be available when and where appropriate and be respectful of the environment (Stock, 1992; Tibben-Lembke & Rogers, 2002). The study of all this product flow in the opposite way and how to deal with all things entailed for the organization is what has been called in recent years Reverse Logistics (Rogers & Tibben-Lembke, 1999, 2001; Dowlatshahi, 2000; Tibben-Lembke & Rogers, 2002; Council of Logistics Management, 2003; Krikke et al., 2003; Stock et al., 2002). Activities of Reverse Logistics require adequate knowledge management in all phases of return of the product that may help to solve problems it faces in all these processes (Wadhwa & Madaan, 2007), and also may approach the current goals of customer satisfaction and business benefit to the legislation for the environment. In this sense, it is fundamental for the organization to have ability to generate new knowledge to reduce the high uncertainty of Reverse Logistics activities (Arrow, 1962; Galbraith & Kazanjian, 1986; Murdick & Munson, 1988; Drucker, 1993). Even with growing importance of both variables, there is a lack of scientific literature that attempt to analyze the relationship between the creation of knowledge and Reverse Logistics and their possible implications. So it is very interesting to analyze the relationship between the creation of knowledge and the importance of Reverse Logistics, and their influence on organizational performance. Using Nonaka and Takeuchi's model of knowledge creation (SECI model, Nonaka & Takeuchi, 1995), we develop and test hypotheses on such relationship using a sample of 284 Spanish firms by examining the direct and indirect effects of knowledge creation and Reverse Logistics upon firm performance. The rest of the paper is set out as follows. The next section considers the previous literature and sets out the hypotheses of this study. The following part is the methodology for the study. Then, the paper presents the results of the empirical study in achieving the goals as those set out above. Discussion and conclusions are provided in the last section. Results of this investigation support that the creation of knowledge positively affects Reverse Logistics and it improves company performance. http://dx.doi.org/10.5755/j01.ee.22.4.719