An object information acquiring apparatus, comprising: a receiver configured to receive an ultrasound wave transmitted to an object and then reflected by the object and a photoacoustic wave generated in the object in response to an illumination with light, wherein the receiver integrally includes a probe that receives the ultrasound wave and a probe that receives the photoacoustic wave; a scanner configured to mechanically move the receiver relative to the object along a path to scan the object; a processor configured to generate structural distribution information on the interior of the object using the ultrasound wave and generate functional distribution information on the interior of the object using the photoacoustic wave; a display; a controller configured to perform a control operation of causing the display to display the structural distribution information and the functional distribution information; and an input unit configured to receive a designation of a region of interest in the object, characterized in that the controller performs a control operation of causing, during a period in which the receiver receives the photoacoustic wave from a partial region formed of at least a part of the object and in which the processor generates the functional distribution information on the partial region, the display to sequentially display the structural distribution information generated by the processor on the basis of the ultrasound wave reflected from the partial region of the object as the scanner moves the receiver to implement scanning in the partial region, the processor generates the functional distribution information using the photoacoustic wave in the region of interest, the input unit is capable of receiving a change of the region of interest while the controller causes the display to sequentially display the structural distribution information, and the scanner changes the path of the receiver on the basis of the changed region of interest. a receiver configured to receive an ultrasound wave transmitted to an object and then reflected by the object and a photoacoustic wave generated in the object in response to an illumination with light, wherein the receiver integrally includes a probe that receives the ultrasound wave and a probe that receives the photoacoustic wave; a scanner configured to mechanically move the receiver relative to the object along a path to scan the object; a processor configured to generate structural distribution information on the interior of the object using the ultrasound wave and generate functional distribution information on the interior of the object using the photoacoustic wave; a display; a controller configured to perform a control operation of causing the display to display the structural distribution information and the functional distribution information; and an input unit configured to receive a designation of a region of interest in the object, characterized in that the controller performs a control operation of causing, during a period in which the receiver receives the photoacoustic wave from a partial region formed of at least a part of the object and in which the processor generates the functional distribution information on the partial region, the display to sequentially display the structural distribution information generated by the processor on the basis of the ultrasound wave reflected from the partial region of the object as the scanner moves the receiver to implement scanning in the partial region, the processor generates the functional distribution information using the photoacoustic wave in the region of interest, the input unit is capable of receiving a change of the region of interest while the controller causes the display to sequentially display the structural distribution information, and the scanner changes the path of the receiver on the basis of the changed region of interest.