The invention relates to an object information acquiring apparatus. The object information acquiring apparatus is used that includes: a light source; a bundle fiber including a plurality of optical fibers; and a processor using an acoustic wave that is generated when light is irradiated on an irradiated surface of an object from an outputting unit of the bundle fiber, and acquiring information from the object, wherein outputting edges of a plurality of sub-bundles, each sub-bundle including a plurality of optical fibers, are arranged in the outputting unit of the bundle fiber, the plurality of sub-bundles include a first sub-bundle arranged in a central part of the outputting unit and a second sub-bundle arranged in a peripheral part of the outputting unit, and the number of optical fibers per unit area of the first sub-bundle is smaller than the number of optical fibers per unit area of the second sub-bundle.