Electrolytic manganese metal residue(EMMR)harmless treatment has always lacked a low-cost and quick processing technology.In this study,surfactants,namely tetradecyl trimethylammonium chloride(TTC),sodium dodecyl benzene sulfonate(SDBS),sodium lignin sulfonate(SLS),and octadecyl trimethy-lammonium chloride(OTC),were used in the solidification of Mn2+and removal of NH4+-N from EMMR.The Mn2+and NH4+-N concentrations under different reaction conditions,Mn2+solidification and NH4+-N removal mechanisms,and leaching behavior were studied.The results revealed that the surfactants could enhance the Mn2+solidification and NH4+-N removal from EMMR,and the order of enhancement was as follows:TTC>SDBS>OTC>SLS.The NH4+-N and Mn2+concentrations were 12.3 and 0.05 mg·L-1 with the use of 60.0 mg·kg1 TTC under optimum conditions(solid-liquid ratio of 1.5:1,EMMR to BRM mass ratio of 100:8,temperature of 20℃,and reaction duration of 12 h),which met the integrated wastewater discharge standard(GB8978-1996).Mn2+was mainly solidified as Mn(OH)2,MnOOH and MnSiO3,and NH4+-N in EMMR was mostly removed in the form of ammonia.The results of this study could provide a new idea for cost-effective EMMR harmless treatment.