A measurement apparatus capable of measuring a position and a size of an absorber with high accuracy, which includes: a light source unit for emitting a pulse beam； an illumination optical unit for leading the pulse beam emitted by the light source unit to an inside of an inspection object； and an acoustic signal detection unit for detecting a photoacoustic signal generated by the pulse beam in which the illumination optical unit includes a first and second illumination optical units that are arranged so that the inspection object is irradiated with the pulse beam from both sides thereof opposingly； and the acoustic signal detection unit is provided so that a detection surface of the acoustic signal detection unit is positioned on the same side as that of one of irradiation surfaces of the inspection object which the first and second illumination optical units irradiate with the pulse beam.
