A photoacoustic wave measurement instrument include a light output unit and at least three photoacoustic wave detection units. The light output unit outputs light. The at least three photoacoustic wave detection units respectively receive photoacoustic waves generated by the light in a measurement object, and convert the photoacoustic wave into electric signals. At least two of the photoacoustic wave detection units have extension directions parallel with or intersecting with each other. At least one of the photoacoustic wave detection units other than the at least two photoacoustic wave detection units has an extension direction intersecting with the extension directions of the at least two photoacoustic wave detection units.
