A route search device, comprising: map data of a road map; a derived route acquisition section (512, 14) configured to acquire a first derived route for a mobile body from an origin point of the mobile body to a destination of the mobile body; characterized in further comprising: a route correction region acquisition section configured to acquire a route correction region corresponding to the first derived route, wherein said route correction region has been set by a user; a place to be passed through setting section (522, 16) configured to set a place to be passed through in the route correction region; a start point and end point setting section (522, 16) configured to set a start point and an end point in the route correction region; a corrected route acquisition section (512, 15) configured to acquire a corrected route, not included in the first derived route, from the start point and passing through the place to be passed through to arrive at the end point; and a route correction section (514, 15) configured to correct the first derived route to a second derived route from the origin point to the destination, constituted by a route from the origin point to the start point, the corrected route, and a route from the end point to the destination, further comprising a pass through frequency storage section 516, 18) configured to store, included in the map data, pass through frequencies of a plurality of mobile bodies that pass through at least one of a plurality of intersections or roads; and wherein the place to be passed through setting section (522, 16), by referring to the pass through frequency storage section, is configured to set at least one of an intersection or road whose pass through frequency is as high as the place to be passed through. map data of a road map; a derived route acquisition section (512, 14) configured to acquire a first derived route for a mobile body from an origin point of the mobile body to a destination of the mobile body; characterized in further comprising: a route correction region acquisition section configured to acquire a route correction region corresponding to the first derived route, wherein said route correction region has been set by a user; a place to be passed through setting section (522, 16) configured to set a place to be passed through in the route correction region; a start point and end point setting section (522, 16) configured to set a start point and an end point in the route correction region; a corrected route acquisition section (512, 15) configured to acquire a corrected route, not included in the first derived route, from the start point and passing through the place to be passed through to arrive at the end point; and a route correction section (514, 15) configured to correct the first derived route to a second derived route from the origin point to the destination, constituted by a route from the origin point to the start point, the corrected route, and a route from the end point to the destination, further comprising a pass through frequency storage section 516, 18) configured to store, included in the map data, pass through frequencies of a plurality of mobile bodies that pass through at least one of a plurality of intersections or roads; and wherein the place to be passed through setting section (522, 16), by referring to the pass through frequency storage section, is configured to set at least one of an intersection or road whose pass through frequency is as high as the place to be passed through. a route correction region acquisition section configured to acquire a route correction region corresponding to the first derived route, wherein said route correction region has been set by a user; a place to be passed through setting section (522, 16) configured to set a place to be passed through in the route correction region; a start point and end point setting section (522, 16) configured to set a start point and an end point in the route correction region; a corrected route acquisition section (512, 15) configured to acquire a corrected route, not included in the first derived route, from the start point and passing through the place to be passed through to arrive at the end point; and a route correction section (514, 15) configured to correct the first derived route to a second derived route from the origin point to the destination, constituted by a route from the origin point to the start point, the corrected route, and a route from the end point to the destination, further comprising a pass through frequency storage section 516, 18) configured to store, included in the map data, pass through frequencies of a plurality of mobile bodies that pass through at least one of a plurality of intersections or roads; and wherein the place to be passed through setting section (522, 16), by referring to the pass through frequency storage section, is configured to set at least one of an intersection or road whose pass through frequency is as high as the place to be passed through.