The fungus Pycnoporus sanguineus MUCL 51321 white rot isolated in Gabon showed a high ability to decolorize and degrade two synthetic dyes. On solid and liquid media, the fungus had different enzyme activities (laccase and manganese (Mn) peroxidase) in the presence of different substrates. At concentrations of 0.05 g/L (Orange G) and 0.3 g/L (reactive blue 4), the respective rates of decolorization of 81% and 97% were observed after 15 days of incubation in liquid media. In the same time interval, changes on the spectra (UV-vis and FTIR) and chromatograms (HPLC) showed that these decolorizations were due to the degradation of dyes by fungus with the production of new compounds. The study revealed the possibility of the use of this fungal strain in the microbial degradation process of synthetic dyes.