Abstract
　The paper deals with the so-called seepage failures of river embankment, taking into consideration the phenomena of no overflow failure of levee and the duration time of flood. From the investigations and experiments the softening and progressive failure are paid attention and its deformation modulus and in shear strength of its constituents soils due to seepage water. The actual permeability of levee is also estimated based on obsorved data.
　Next the paper explains analyses of saturated-unsaturated seepage through the four typical types of levee which are classified from the consideration of historical process of construction work, taking aim at the establishment of stability evaluation of levees.

*京都大学工学部
Faculty of Engineering, Kyoto University
*岐阜大学工学部
Faculty of Engineering, Gifu University