Disclosed is a medical device which displays an object relating to an image considered to include an indication relating to a pathological entity, such as, for example, a lesion, on a terminal on which a medical image is displayed, and a method for displaying a medical image by using the same. The medical device includes a display device, a communication device which communicates with an external device, and a controller which displays an image which includes the indication relating to a pathological entity on the display device when the communication device receives image information relating to a subject.