Please cite this article as: M. Sakhaii, R. Tavakkoli-Moghaddam, M. Bagheri, B. Vatani, A robust optimization approach for an integrated dynamic cellular manufacturing system and production planning with unreliable machines, Appl. Math. Modelling (2015), doi: http://dx.Abstract:In this study, a robust optimization approach is developed for a new integrated mixed-integer linear programming (MILP)model to solve a dynamic cellular manufacturing system (DCMS) with unreliable machines anda production planning problemsimultaneously. This model is incorporated with dynamic cell formation, intercell layout, machine reliability, operator assignment, alternative process routings and production planning concepts. To cope with the parts processing time uncertainty, a robust optimization approach immunized against even worst-case is adopted. In fact, this approach enables the system's planner to assess different levels of uncertainty and conservation throughout planning horizon. This study minimizes the costs of machine breakdown and relocation, operator training and hiring, inter-intra cell part trip, and shortage and inventory. To verify the performance of the presented model and proposedapproach, some numerical examples are solved in hypothetical limits using the CPLEX solver. The experimental results demonstrate the validity of the presentedmodel and the performanceof the developed approach in finding an optimal solution. Finally, the conclusion is presented.