1. An insertion support system comprising: a virtual image generating portion for generating a virtual image of a body cavity path within a subject based on the image data of a three-dimensional region of the subject; a route starting-point setting portion for setting a starting-point of an insertion route of an endoscope to the body cavity path within the subject; a region-of-interest setting portion for setting a region of interest within the subject; a route extracting portion for extracting a plurality of insertion routes to a position of the body cavity path positioned near the region of interest from the starting-point; and a route verifying portion for verifying the plurality of insertion routes extracted by the route extracting portion, wherein the route verifying portion includes: a position specifying portion for specifying an arbitrary position on the insertion route extracted by the route extracting portion; and a display portion for displaying the virtual image in the position specified by the position specifying portion.