PROBLEM TO BE SOLVED: To obtain a solidification material satisfying low bleeding property and low viscosity at the same time and capable of adjusting solidification strength from extremely weak strength to high strength according to mixing ratio by mixing a cement and a baked fine powdery non-swelling clay. SOLUTION: This solidification material is obtained by mixing a cement and a baked fine powdery non-selling clay, which is prepared by baking a clay at 200-700 deg.C and has a degree of swelling of <=3.5cc/g and a degree of fineness of 5000-9000cm<2> /g in terms of Blaine value, preferably at a weight ratio of (1:9) to (8:2). The solidification material is useful for foundation improvement construction, liquefaction counter measure construction, back-filling construction, high cut-off underground continuous wall making construction, etc.
