Energy dissipation and scour control are all the key issues for the design of hydraulic structures.On the basis of the high energy dissipation for the multiple slit-type energy dissipaters (M-STED) developed by the authors,in this work,the characteristics of the scour hole for the M-STED were experimentally investigated through three sets of those physical models with five cases and a scour hole form index was proposed.The results show that,the M-STED results in not only the high energy dissipation but also the mild upstream slope of the scour hole thanks to the scour hole form index of larger than 0.5,which is in favor of the safety of the release works.