A medical device 1 includes: an insertion portion to be inserted into a bronchus 9 of a subject 7, a CT image data storing section 15 configured to store previously acquired three-dimensional image data of the subject 7 a position calculation section 20 configured to calculate a position and a direction of a distal end portion 2C of the insertion portion 2A in the bronchus a route generation section 18 configured to generate an insertion route R for inserting the distal end portion 2C to a target position 9G through the bronchus 9, based on the three-dimensional image a tomographic image generation section 14 configured to generate a tomographic image based on the position and the direction of the distal end portion 2C, from the three-dimensional image data a superimposed image generation section 12 configured to generate a superimposed image PW1 in which the insertion route R is superimposed on the tomographic image PO and a display section 4 configured to display the superimposed image PW1.
