A particle for treatment and repair of soil contamination is mainly composed of potassium ferrate and an inorganic cementitious material. The inorganic cementitious material is a powdery air-hardening or hydraulicity inorganic cementitious material. The potassium ferrate and the inorganic cementitious material are mixed according to the mass fraction of 1:5-50. After mixing is carried out, the particle with the particle diameter ranging from 2 mm to 5 mm is formed by means of vibration of a vibration screen, the particle is wrapped by a water-soluble film, and the water-soluble film is heated to be shrunk and then is closely attached to the outer surface of the particle. Also disclosed is a method for repairing soil by using the particle. When the particle is mixed with an ozone water solution is adopted.