Waste-olive-waters arising from the solid-liquid processing system were degraded in agitated liquid cultures of the white-rot fungus Lentinus edodes. About 45% of biodecolouration and 75% of fetal organic carbon reduction were achieved within 4 days. Over the same period, the content of total phenols was reduced by 66%. The release of exo-enzymes involved in the metabolism of phenolic compounds (phenol-oxidases and Mn-peroxidase) was greatly enhanced with respect to the control. A highly-significant correlation was observed between decolourization, total organic carbon and total phenols.