Conductive yarns and conductive wires having insulating properties at least on their surfaces are plain-woven as warps and wefts, thus manufacturing a unidirectionally conductive fabric in which neighboring conductive yarns are not electrically in contact with each other. A pair of electrodes is connected to ends of the conductive yarn, and polymeric insulating layers are laminated on both surfaces of the unidirectionally conductive fabric, thus manufacturing an electric heating sheet. Moreover, by forming polymeric covering layers having a thermal fuse function, a temperature-detecting function and a temperature controlling function on the unidirectionally conductive fabrics, highly durable and safe electric heating sheets are manufactured.