An in-vivo image acquiring apparatus includes an imaging unit which is introduced inside a subject and picks up image information inside the subject, an illuminating unit which illuminates an imaging portion imaged by the imaging unit, a transmission processing unit which performs a process to wirelessly transmit the image information acquired by the imaging unit to an external apparatus. A light-control unit determines light-control amount information based on brightness of the image information acquired by the imaging unit, and performs a control of light control of the illuminating unit according to the light-control amount information. Further, the transmission processing unit performs a process to wirelessly transmit the image information acquired by the imaging unit along with the light-control amount information used for the control of light-control.