The invention discloses an inorganic mixture prepared by a lime dried sludge. The lime dried sludge product is mixed with cementing materials such as fly ash, lime, cement and the like for stabilizing fine-grained soil to obtain a mixture, the prepared mixture is used for pavement sub-bases of second level and below second level roads or city sub-arterial roads and lower level roads, and replaces a common inorganic mixture. Performance indexes of the lime dried sludge are that: the effective calcium and magnesium content is greater than 20%, the content of particles with the particle size of 5 mm or less is greater than 65%, and the moisture content is 20% to 40%. The inorganic mixture provided by the invention can consume the city dried sludge with large scale, solves sludge disposal problem, and prevents secondary pollution; the inorganic mixture has good mechanical and durability properties, and can meet application requirements of the second level and the lower level road sub-bases; and the inorganic mixture as city solid waste has much lower raw material price than natural stone material, and thereby reducing production cost.