Rhodamine B (RhB) was degraded by activating potassium bisulfate by preparing MnFe₂O₄- reducing graphene oxide (RGO) composite activator.The effect of pH,temperature,potassium peroxymonosulfate content and MnFe₂O₄--RGO dosage on the degradation efficiency was investigated by preparing MnFe₂O₄--reduced graphene oxide (RGO) composite surfactant and activating potassium persulfate to degrade rhodin B (RhB).The results showed that the optimal reaction conditions of MnFe₂O₄-RGO catalyst with RGO doping mass fraction of 7% were as follows: when pH=7,temperature 25 ℃,n(RhB)∶n(KHSO₅)=1∶15,the decolorization rate of RhB solution reached 95% and the activation energy of the degradation reaction was 30.39 kJ/mol.The degradation effect of MnFe₂O₄-RGO was much higher than that of MnFe₂O₄ alone,probably because RGO promoted the dispersion of MnFe₂O₄and provided more reactive sites for RhB.The degradation rate of RhB by MnFe₂O₄-RGO still be maintained above 90% after 5 times of repeated use.