Provided is an electric conductive fiber structure that can maintain high electric conductivity even after repeated washing and can even be used for a biosignal acquisition electrode. The electric conductive fiber structure of the present invention includes a woven or knitted fabric containing an electric conductive polymer. The electric conductive fiber structure includes an electric conductive resin containing the electric conductive polymer filled in gaps between single fibers included in a fiber structure and has an area ratio of the electric conductive resin existence in an area of 15 to 30 µm from a surface of 15% or more when a cross section in a thickness direction of the fiber structure is observed.