To obtain a cement solidifier that has high mechanical strength, can be used in a variety of uses and causes no adhesion to the treatment machine by using a cement produced from garbage incineration ash as a raw material and admixing calcium chloroaluminate thereto.

The cement solidifier for calcination ash solidification is used in an amount of 5-20 pts.wt. per 100 pts.wt. of the calcination ash. The solidifier is composed mainly of garbage incineration ash, for example, the incineration ash of urban refuse and contains calcium chloroaluminate. This cement solidifier is produced by admixing 5-50 pts.wt. of calcite powder and 2-40 pts.wt. of plaster as adjusting components to 100 pts.wt. of refuse incineration ash and firing the mixture at 1,100-1,500°C to form the objective clinker. The resultant cement solidifier has a plane specific surface area of 3,000-5,000cm2/g and contains 5-50wt.% of calcium chloroaluminate as a mineral component.