Abstract: In order to solve the Flexible Flow shop Scheduling Problem（FFSP），a discretized dragon algorithm was proposed. In view of the outstanding performance of dragonfly algorithm on continuous optimization problems，it was now applied to the discrete optimization problems. This new algorithm adopted the ROV（Ranked Order Value）coding method， converted the continuous position vector into a sequence of jobs，and a decoding method using FAMFR（First Available Machine First Rule），converted each dragonfly individual into a feasible schedule and calculated its total completion time. These two improvements make the algorithm suitable for solving FFSP. Finally，the algorithm was applied to a FFSP instance. Compared with the genetic algorithm，the experimental results show that the proposed algorithm reduces the required processing time by 8. 5%，which verifies the effectiveness of the algorithm for solving FFSP.