Abstract: Vehicle routing is a key success factor in logistics problems. A variation of Vehicle Routing problem (VRP), the heterogeneous fixed fleet VRP in which the vehicles available for distribution activities are characterized by different capacities and costs, is tackled. A hybrid firefly algorithm for optimizing the routing of heterogeneous fixed fleet of vehicles in logistics distribution systems is presented. The principles and key steps of the proposed firefly algorithm are introduced in detail. Experimental results from solving the heterogeneous fixed fleet vehicle routing problem when tested on benchmark datasets are demonstrated. Moreover, the algorithm is compared with other algorithms solving similar problems in order to prove the effectiveness of the proposed hybrid firefly algorithm.