A physiological signal sensing system and method are provided. The physiological signal sensing system includes a physiological signal sensing device and a signal processing device. The physiological signal sensing device includes a plurality of sensing electrodes. The sensing electrodes are used to contact the surface of an organism to sense a plurality of physiological signals. The signal processing device is coupled to the physiological signal sensing device to receive the physiological signals. The signal processing device compares these physiological signals with the reference physiological signal pattern to obtain a comparison result. The signal processing device selects a selected electrode pair from the sensing electrodes based on the comparison result. The signal processing device uses the selected electrode pair to perform physiological signal measurement on the organism during a normal operation period.一種生理訊號感測系統與方法。所述生理訊號感測系統包括生理訊號感測裝置以及訊號處理裝置。生理訊號感測裝置包括多個感測電極。這些感測電極用以接觸生物體的表面，以感測多個生理訊號。訊號處理裝置耦接生理訊號感測裝置，以接收這些生理訊號。訊號處理裝置將這些生理訊號相較於參考生理訊號圖譜，以獲得比較結果。訊號處理裝置依據比較結果而從這些感測電極中選出一個經擇電極對。訊號處理裝置在通常操作期間使用該經擇電極對對生物體進行生理訊號量測。
