A pulse wave detection device acquires an image. The pulse wave detection device extracts a living body region included in the image. The pulse wave detection device generates a signal from time series data of a pixel value included in a partial image of the image corresponding to the living body region. The pulse wave detection device calculates a variation index for evaluating a degree of disturbance of a pulse wave included in the signal. The pulse wave detection device controls whether to output the signal by using the variation index.