The invention discloses an acidified bentonite. The technical scheme is as follows: the acidified bentonite is composed of bentonite, sulfuric acid, instant sodium silicate, polyvinyl alcohol, hydroxypropyl methylcellulose and sodium carbonate. The production method of the acidified bentonite comprises the following steps: inputting acidified bentonite materials into a mill, and milling into powder, thereby obtaining the acidified bentonite. The composite proportioning is performed after acidification, thereby avoiding the chemical reaction between the sulfuric acid and the instant sodium silicate, polyvinyl alcohol, hydroxypropyl methylcellulose and sodium carbonate, fully displaying the respective characteristics of the raw materials in the formula, and ensuring the inherent quality of the acidified bentonite. The acidified bentonite has favorable adsorbability, high-temperature stability and lubricating property, and the water absorptivity, colloid index, plasticity, expansion coefficient, colloid viscosity and thixotropy are greatly enhanced. The acidified bentonite is suitable for producing products in the fields of paints, aviation, metallurgy, chemical fibers, petroleum, firefighting and the like.