A pulse photometer includes: a first variation acquirer acquiring a first variation corresponding to a light attenuation variation of a first light beam due to pulsation of blood in a subject based on a first intensity signal corresponding to an intensity of the first light beam transmitted through or reflected from a body of the subject and having a first wavelength; a second variation acquirer acquiring a second variation; a third variation acquirer acquiring a third variation; a concentration calculator calculating a blood light absorber concentration based on the first variation and the second variation; an estimated value calculator calculating an estimated value of the third variation based on the first variation and the second variation; and an evaluator evaluating reliability of a calculated value of the blood light absorber concentration based on the third variation and the estimated value.