Degradation of rhodamine B by Fe(0)-based Fenton process with H 2 O 2 was investigated. The effects of H 2 O 2 dose, Fe(0) dose, initial concentration of rhodamine B and initial pH value on the degradation of rhodamine B were examined. The results showed that the degradation and mineralization of rhodamine B occurred with low dose of H 2 O 2 and Fe(0). The intermediates of rhodamine B were analyzed with UV–Vis spectrophotometry and ion chromatography and the mechanism of oxidative degradation of rhodamine B was also discussed. The reactive oxygen species (·OH) produced in Fe(0)-based Fenton process with H 2 O 2 is the key to the degradation of rhodamine B by ways of N-de-ethylation, chromophore cleavage, ring-opening and mineralization.