The invention discloses an ecological restoration method of a tailings reservoir. The method comprises the steps as follows: S1: closing the tailings reservoir and measuring the size of the tailings reservoir; S2: pumping dry water in the reservoir; S3: air drying the tailings reservoir; S4: leveling the tailings reservoir, and adding a stabilizer to the tailings reservoir for neutralization; S5: filling the tailings reservoir with soil and performing rotary tillage; S6: planting crops. The ecological restoration method of the tailings reservoir can reduce the influence of structural characteristics of tailings on the crops, restores the ecological environment of the abandoned tailings reservoir, and returns the field to agriculture.