A subject-information acquiring apparatus includes a light source a bed having a holder holding an examined portion of a subject, the bed being configured to support the subject acoustic wave detectors configured to detect acoustic waves and output electric signals, the acoustic waves being generated when the examined portion is irradiated with light from the light source a supporting member configured to support the acoustic wave detectors such that a direction of maximum reception sensitivity of at least some acoustic wave detectors and a direction of maximum reception sensitivity of other acoustic wave detectors different from the at least some acoustic wave detectors are different and are directed toward a specific region and a signal processing unit configured to acquire information about the inside of the examined portion on the basis of the electric signals. The holder can be changed in shape to fit a shape of the examined portion.
