A travel supporting control system comprising: a traveling-lane keeping assist control unit that performs traveling-lane keeping assist control, which is either assistance of driving of a driver of a vehicle or control of traveling of the vehicle, so that the vehicle travels without deviating from a lane along which the vehicle travels; an obstacle detecting unit that detects an obstacle in front of the vehicle; a virtual lane setting unit that sets a virtual lane which is a region where the vehicle travels in the lane narrowed by the obstacle detected by the obstacle detecting unit; a virtual lane width calculating unit that calculates a virtual lane width which is a width of the virtual lane set by the virtual lane setting unit; and a traveling-lane keeping assist control stopping unit that stops the traveling-lane keeping assist control performed by the traveling-lane keeping assist control unit when the virtual lane width calculated by the virtual lane width calculating unit is equal to or smaller than a threshold value, characterized by a driver intention detecting unit capable of detecting a direction, in which the driver is going to make the vehicle travel, on the basis of an operation of the driver of the vehicle; and a virtual lane selecting unit that when the virtual lane setting unit sets a plurality of virtual lanes divided in the width direction of the virtual lane by the obstacle detected by the obstacle detecting unit, selects the virtual lane in the direction in which the driver is going to make the vehicle travel, which is detected by the driver intention detecting unit, from the plurality of divided virtual lanes, wherein the traveling-lane keeping assist control stopping unit stops the traveling-lane keeping assist control performed by the traveling-lane keeping assist control unit when the virtual lane width of the virtual lane selected by the virtual lane selecting unit is equal to or smaller than the threshold value. a traveling-lane keeping assist control unit that performs traveling-lane keeping assist control, which is either assistance of driving of a driver of a vehicle or control of traveling of the vehicle, so that the vehicle travels without deviating from a lane along which the vehicle travels; an obstacle detecting unit that detects an obstacle in front of the vehicle; a virtual lane setting unit that sets a virtual lane which is a region where the vehicle travels in the lane narrowed by the obstacle detected by the obstacle detecting unit; a virtual lane width calculating unit that calculates a virtual lane width which is a width of the virtual lane set by the virtual lane setting unit; and a traveling-lane keeping assist control stopping unit that stops the traveling-lane keeping assist control performed by the traveling-lane keeping assist control unit when the virtual lane width calculated by the virtual lane width calculating unit is equal to or smaller than a threshold value, characterized by a driver intention detecting unit capable of detecting a direction, in which the driver is going to make the vehicle travel, on the basis of an operation of the driver of the vehicle; and a virtual lane selecting unit that when the virtual lane setting unit sets a plurality of virtual lanes divided in the width direction of the virtual lane by the obstacle detected by the obstacle detecting unit, selects the virtual lane in the direction in which the driver is going to make the vehicle travel, which is detected by the driver intention detecting unit, from the plurality of divided virtual lanes, wherein the traveling-lane keeping assist control stopping unit stops the traveling-lane keeping assist control performed by the traveling-lane keeping assist control unit when the virtual lane width of the virtual lane selected by the virtual lane selecting unit is equal to or smaller than the threshold value.