Provided is a capsule endoscope apparatus, receiving apparatus, and capsule endoscope system that can reduce the consumption of a battery. A capsule endoscope apparatus 3 to be introduced into a subject includes an imaging unit 303 that captures an image of the subject, and generates image data of the inside of the subject, a transmission unit 306 that transmits a wireless signal including the image data to the outside, a receiving unit 308 that receives, from the outside, a control signal to instruct the operation of the capsule endoscope apparatus 3, and a capsule controller 312 that activates the receiving unit 308 in synchronization with a transmission timing when the transmission unit 306 transmits the wireless signal.