We propose a new method that measures skin conductance over clothes to nonintrusively monitor the changes in physiological conditions affecting skin conductance during daily activities. We selected the thigh-to-thigh current path and used an indirectly coupled 5-kHz AC current for the measurement. While varying the skin conductance by the Valsalva maneuver method, the results were compared with the traditional galvanic skin response (GSR) measured directly from the fingers. Skin conductance measured using a 5-kHz current displayed a highly negative correlation with the traditional GSR and the current measured over clothes reflected the rate of change of the conductance of the skin beneath.