Today, due to manufacturing SMEs resource and financial constraints, using the open innovation is one of the basic approaches in these companies. The research aims to present a multilevel model for success factors of open innovation implantation.

the first stage, the effect of each success factor of Open Innovation on the others determined by fuzzy revised DEMATEL based on views of 12 experts; Then, Interpretive structural model of studied factors plotted in 3 level called base, strategic, and operational layer respectively.

In terms of importance open innovation success factors divided by 3 levels called base, strategic, and operational layer. The most significant level dedicated to the base layer including Economic Factors as the most influential indicator on the others, Universities, research Institution, and IT Support System. Competitors, Partners, Organizational Strategy, Organizational Learning, Employees and Reward Systems in the strategic layer and suppliers, organizational structure, and Ecological issues (secluded factor in the model) are at the operational layer. Moreover, success factors are ranked based on effectiveness, and their causal nature is also identified.

Given the importance of results, managers of manufacturing SMEs advised to reduce the risk of R&D and increase the odds of organization survival by changing opening their innovation process. Besides, developing of partnership with universities, research institutes, and Strengthening the IT's infrastructure could accelerate the achievement of innovative goals.