Herbicide 2,4-D is one of the most widely used in the world. In this way, its presence on different bodies of water has been reported. In this paper the efficiency of horizontal-subsurface flow constructed-wetlands for 2,4-D removal in aqueous solutions was assessed. Wetlands were constructed using fiberglass, and grown with Phragmites australis. The influent consisted of synthetic wastewater under different 2,4-D and glucose initial concentrations. Results indicated that, under the evaluated experimental conditions, 2,4-D extent of removal was between 71.0 and 99.0%. In general, it can be noted that an increase in the herbicide concentration reduces the removal efficiency, probably due to a toxic effect on the biological component. On the other hand, the influent dissolved organic carbon (DOC) initial concentration had a significant effect on the removal of both, the herbicide and the organic matter content in the system, demonstrating that this parameter has a significant effect on this kind of biological methods for water treatment. Finally, it can be concluded that constructed wetlands are a viable alternative for the treatment of wastewater contaminated with the herbicide 2,4-D.