A capsule endoscope 10 includes: an in vivo information acquiring section 26 that acquires information on an inside of a body of a subject a battery 19 that supplies power a power source switch 25 that turns on/off power supply from the battery 19 to the in vivo information acquiring section 26 a detection section 20 that upon detection of introduction to the inside of the body of the subject, outputs a detection signal and a control section 21 that controls the power source switch 25 according to the detection signal.
