Capillary wetting and hygroscopicity in fibrous assemblies were investigated from the practical viewpoint.using a device newly developed. The change in electric conductivity by capillary rising of aqueous solution with time was measured using plugs of cotton, wool, nylon and polyester fabrics as well as untreated and siliconized cellulose filter papers in a cylindrical Teflon cell. Their hygroscopicities were also examined as the change in electric resistance using the same cell and the Super Megohmmeter by keeping the water head in the position of 5 mm below the plug. It was found that the difference in their wettabilities and hygroscopicities was generally understood in terms of their chemical structures. The wool fabric and the siliconized cellulose filter paper were found to have hygroscopicity in spite of their water repellency. Thus, the device will be available for practical tests of capillary wetting in fibrous assemblies and hygroscopicity of fibers.