The effect of a fluorosulfonic acid (FSO3H) aqueous solution on decomposing the chrysotile asbestos fibers was investigated by using FT-IR, XRD, and XPS. From the equilibrium of FSO3H in an aqueous medium (FSO3H + H2O = HF + H2SO4), the resulting H2SO4 had a strong affinity for the external Mg(OH)(2) layers in the tubular, scroll-like chrysotile structure. This acid-base reaction led to the precipitation and lixiviation of MgSO4 . H2O, MgO, and Mg2+ ion. Once the breakage of the outer Mg(OH)(2) layers occurred, HF readily diffused into the inner silicious layers and then reacted with silicates, converting them into SiO2 hydrate and H2SiF6, while the ionic reaction between lixiviated Mg2+ and F- resulted in precipitating MgF2, thereby destroying the fibrous nature of the asbestos. An optimum combination of HF and H2SO4 contributed significantly to enhancing the rate of conversion of asbestos into nonfibrous materials in a short treatment time without any physical agitation.