To provide a foldable paper-made detector that is thinner, lighter in weight, and convenient to carry, used for a device for measuring breath odor, and is also very sanitary due to disposable.

In the a foldable paper-made detector used for a device for measuring breath odor, abnormal odor is detected such that a polyanglar tube-like body preliminarily folded is made three-dimensionally to form a polyanglar tube, then a band-like breathable detector is passed through an aperture, with both lateral faces already being cut by insections, by moving it continuously or by inserting it frame by frame, and finally, samples for the detector, each frame of which is sequentially numbered and has different feature, are used for the detection of changes by breath odor.