PROBLEM TO BE SOLVED: To provide a hardening material and a hardening material liquid which are excellent in flash setting properties, with a gelling time of 10 s or shorter, and are reduced in stirring time in producing individually the main material liquid and the hardening material liquid, an agent for soil property stabilization, a production method of the agent and a ground stabilization method.SOLUTION: A hardening material is used for hardening a main material liquid comprising a hydraulic cement other than alumina cement, gypsum, lime and water and contains alumina cement, an inorganic carbonate and an alkali metal aluminate.
