The present invention relates to a sensing device and a sensing method for continuously or intermittently quantifying a concentration of analyte. A measurement signal correlated with a concentration of analyte is sequentially acquired by use of a sensor (12). A filter processing is performed on a time sequence of the measurement signal acquired by the sensor (12) in a frequency domain via one type of filter among a plurality of types of filters (48, 49, 84). One type of filter used in the filter processing is switched depending on the amount of temporal change of the measurement signal.
