Developing countries demand a sewage treatment plant with low-cost processes that are viable in warm climates. The UASB (upflow anaerobic sludge blanket) associated with the trickling filter (TF) would meet this requirement. However, there is still a need for studies aimed at the use of new support media. Based on this, the use of expanded polystyrene (EPS) as a support media in TF was evaluated in this study. As a result, the TF filled with EPS presented a final effluent with quality similar to reactors filled with crushed stone or patented materials. The density of EPS (6.56 ± 0.30 kg m−3), the void ratio (61.7 ± 2.1%), and the mean surface area (201.9 ± 14.9 m2 m−3) once again demonstrate that EPS has characteristics similar to other alternative or patented materials. Therefore, we found that EPS can be another alternative material to be used in sewage treatment, and also that one could give an appropriate destination to a portion of this material, which is currently still discarded in landfills.