Based on the related experimental results at home and abroad，the study on energy dissipation characteristic of the stepped spillway was systematically conducted by a hydraulic model. The affecting factors and regularities of energy dissipation ratio for the stepped spillway are summarized in this paper. The study results demonstrate that the ratio of energy dissipation is not basically relevant to the spillway slope，but has a quantitative relation with the discharge of per unit width，step height and step numbers.