The present invention provides an endoscope system having a scope unit including an image capturing unit, a nonvolatile memory storing specific parameters of the scope unit, an image processing device, a first data transmission unit in the image processing device, transmitting a first packet including a signal for requesting, a first data reception unit in the image processing device, receiving a second packet based on the first packet and includes the specific parameters or the realtime information, a second data reception unit in the scope unit, receiving the first packet, a data selection unit selecting whether the second packet is transferred either in a first data format or in a second data format based on the signal that is included in the first packet received by the second data reception unit, and a second data transmission unit transmitting the second packet to the first data reception unit.
