A long term physiological signal sensing patch, including a water protective film, an electrode layer, a conductive hydrogel layer, a block layer and a first attaching layer. The water protective film provides functions of electrical insulation, stickiness and water protection. The electrode layer includes at least two electrodes attached to the bottom of the water protective film. The conductive hydrogel layer configured beneath the electrodes is electrically conductive and sticky. The block layer is under the electrodes to block water, and accommodates the conductive hydrogel layer. The first attaching layer is provided around the block layer. Therefore, the sensing patch can be attached to the human body for a long period of time to sense physiological signal, which is further transmitted to the external apparatus for more detailed analysis, calculation or display.
