en Research Paper Research Paper A dynamic programming fuzzy rule-based (DPFRB) model for optimal operation of reservoirs system is presented in this paper. A deterministic Dynamic Programming (DP) model is used to develop the optimal set of inflows, storage volumes, and reservoir releases. These optimal values are then used as inputs to a Fuzzy Rule-Based (FRB) model to derive the general operating policies. Subsequently, the operating policies are evaluated in a simulation model while optimizing the parameters of the FRB model. The algorithm then gets back to the FRB model to establish the new set of operating rules using the optimized parameters. This iterative approach improves the value of the performance function of the simulation model and continues until the satisfaction of predetermined stopping criteria. The DPFRB performance is tested and compared to a model which uses the multiple regression based operating rules. Results show that the DPFRB performs well in terms of satisfying the system target performances. reservoir operations, dynamic programming, and fuzzy inference system 67 77 http://ijce.iust.ac.ir/browse.php?a_code=A-10-717-1&slc_lang=en&sid=1 S.J. Mousavi jmosavi@aut.ac.ir 180031947532846005846 180031947532846005846 Yes K. Ponnambalam 180031947532846005847 180031947532846005847 No F. Karray 180031947532846005848 180031947532846005848 No