The invention provides an environment-friendly silt curing agent, which is manufactured through the following steps: one or two among fly ash, calcium sulfate, sodium sulfate, sodium carbonate and potassium carbonate, one or two among slag, slag combination, potassium hydroxide, calcium oxide, sodium silicate or silicon dioxide, one or two among carbide slag, lime or gypsum, as well as one or two among triethanol amine surfactant, calcium lignosulfonate or sodium lignosulfonate form a plurality of optimal compound formulations according to respective attributes, are optimized, compounded, ground till the Brinell specific surface areas are between 300 and 900 m2/kg respectively and then mixed, wherein particle sizes are between 0.00040 and 0.5 mm. As a large amount of waste is utilized, the curing agent saves raw materials, solves the problems about waste discharge and environmental pollution, controls waste through waste, and has important significance to environmental protection. The invention aims to provide the environment-friendly silt curing agent which has strong adaptability to a plurality of types of silt and soil, is good in curing effect, good in durability after curing and capable of utilizing industrial waste, and can be widely applied to fill engineering, embanking or embankment reinforcement engineering, road engineering and other fields.