Aspergillus niger AN 400 was tested in the treatment of a synthetic water containing 2,4-dinitrophenol (2,4-DNP) by operating batch reactors with immobilized biomass. The treatment was carried out in two stages: 1) accomplished growth of fungal inoculum Aspergillus niger AN 400, and 2) the biomass was immobilized on a support at a concentration of 2 x 106 mL-1 of spores. The reaction times (RT) were 168, 48, 24 and, 8 h. The variables analyzed were COD, pH and nitrogen fractions. Decay temporal (RT168 h) of 2,4-DNP and COD adjusted to the first-order model. The higher removal efficiency 2,4 DNP was 96% and COD was 83%. There was a decrease of sequencing batch reactor SBR efficiency when RT were 8 h. The use of Aspergillus niger AN 400 may be an alternative treatment of wastewater containing nitrophenolic compounds.