Frictional Force of fabrics was measured as a function of the water content of fabrics. The frictional force was compared with the soarked area of the boundary face between fabrics and a plastic plate. It was found that the frictional force rises sharply when the boundary face is soarked completly and after it reaches a maximum value, decreases quickly. The drop-off of the frictional force was observed from the measurement using the liquid solusion of a weak surface tension.