A method and an apparatus for acquiring biological information, and a wrist watch-type terminal using the same, are provided. The apparatus includes a first detector configured to irradiate a living body with a first light of a first wavelength, and detect a second light that is reflected from the living body, and a second detector configured to irradiate the living body with a third light of a second wavelength, and detect a fourth light that is reflected from the living body. The apparatus further includes a processor configured to determine a pulse wave of the living body based on a subtraction value of subtracting a detection signal that is determined by irradiating the third light of the second wavelength from a detection signal that is determined by irradiating the first light of the first wavelength.