This paper presents characteristics of Fish passages installed in Sabo work. In Kannagawa, blanch of Tone River, Gumma Pref., Japan, there are many Sabo dams and groundsills. A lot of stones and driftwoods have been transformed during flood stages, and flush system and stabilization of fish passage are required for the installation of fish passage. Also, as a discharge of river greatly changes, migration route in fish passage must be kept under a wide range of discharges. In order to satisfied with the above requests, a pool type fish passage with trapezoidal section and a fish passage with stacking boulders were constructed in groundsill. In the case of the pool type fish passage, as the shape of weir, compound cross section is formed. The main flow passes through the center portion for small discharge, and the flow at both side of weir is formed like a sheet flow in which juvenile fishes can migrate upstream. If the discharge becomes large, the flow at both side of weir becomes optimal flow for the upstream migration of swimming adult fishes. Last year, a big flood with lot of gravels and driftwoods was passed through the groundsill, the sediment could not be found in the pool after the flood. In the case of the fish passage with stacking boulders, big rocks with 0.7 to 1.2 m diameters were utilized, and a masonry of stacking boulders was applied in the fish passage. The flow passing through each boulder is varied for the change of discharges, and the migration route might be changeable. In this case, one month was passed since the construction, and field investigations for the migration of aquatic animals must be required for several types of discharges. In the conference, more information might be supported.