In a body surface bio-potential sensor, and an apparatus for detecting biomedical signals having the same, the body surface bio-potential sensor includes a flexible membrane having a wire layer, a plurality of electrodes attached on a first surface of the membrane at predetermined intervals, each of the plurality of electrodes having a plurality of needles on a surface thereof, each of the plurality of needles having a predetermined height, and a cohesive layer covering the first surface of the membrane, the cohesive layer exposing regions of the flexible membrane corresponding to positions of the plurality of electrodes.