An apparatus for detecting a narrow road in front of a vehicle includes: a narrow road determination processor configured to generate circular arcs passing between obstacles, select a circular arc closest to the middle of the obstacles among the generated circular arcs, and generate an offset curve which is a circular arc having the same central point as the selected circular arc and contacting a corresponding obstacle at left/right sides of the selected circular arc, based on driving information and specification information of the vehicle, and then to determine that a road is a narrow road when a width between the two offset curves does not exceed a threshold value.