Lean manufacturing has been the primary approach for creating highly efficient manufacturing processes since the early 1990s. It may be very successful due to its effectiveness in reducing complexity and heading off unnecessary works or waste. At present, the term Industry 4.0 depicts a vision of the future manufacturing system. Previous researches indicate the possibility to integrate and combine the lean approach and industry 4.0 system. Previous researches suggest that there are positive relationships between the two concepts. Besides, they conclude that integrating the lean approach and industry 4.0 leads to a greater cost reduction than implementing only one of them. The current paper summarizes and proposes a conceptual framework that can guide the implementation of the integration of lean manufacturing and industry 4.0.