A method of asbestos detoxification in which an asbestos-containing waste material in any form is made harmless while preventing asbestos particles or dust from flying or scattering. The asbestos content can be easily reduced in a short time to 0.1 wt. % or lower, which is prescribed by the Ministry of Health, Labor, and Welfare. The waste can be perfectly made harmless. Also provided is an aqueous solution for asbestos detoxification which is for use in the method. The method of asbestos detoxification comprises: bringing an asbestos-containing waste material into contact with an aqueous treating solution containing at least one fluoride ion source selected from the group consisting of the fluorides of alkali metals, alkaline earth metals, and ammonia and hydrofluoric acid and further containing at least one mineral acid selected from the group consisting of hydrochloric acid, sulfuric acid, and nitric acid so that the aqueous treating solution has a pH of 1 or lower; and allowing the resultant mixture to stand or stirring it while adding the mineral acid so as to keep the pH of the aqueous treating solution at 1 or lower. Thus, the asbestos in the asbestos-containing waste material is made harmless.