Provided is an endoscope device and a method of operating the endoscope device. The endoscope device includes: a knob driving part configured to be driven in a mode selected by an operator from either of an automatic mode and a manual mode; a bending part connected to the knob driving part and configured to change a position of a distal end of the endoscope device by driving of the knob driving part, a power generating part configured to provide power to the knob driving part; and a power transmitting part configured to drive the power generating part according to a manipulation of the knob driving part.