A vehicle location estimation apparatus for estimating a location of another vehicle in the periphery of a host vehicle, the vehicle location estimation apparatus comprising: an azimuth acquisition device that acquires an azimuth of a direction of travel of the host vehicle; a road radius estimation device (13, 14, 21; 22; 23; 24; 25) that estimates a curvature radius of a road on which the host vehicle is traveling; an other vehicle location acquisition device that acquires the location of another vehicle; and an other vehicle azimuth acquisition device that acquires an azimuth of a travel path direction in which the other vehicle is travelling characterized by a determination device (21; 22; 23; 24; 25) that arranges the other vehicle on a coordinate system, an origin of which is a position of the host vehicle, and an axis of which is a travel path direction in which the host vehicle is travelling, and that determines whether or not a road on which the other vehicle is travelling is the same as a road on which the host vehicle is travelling and a travel path direction in which the other vehicle is travelling is the same as the travel path direction in which the host vehicle is travelling, by setting a location threshold value and an azimuth threshold value taking account of a width of a road, error in the acquired location of the other vehicle, error in the estimated curvature radius of the road, change in a curvature of a travel course of the host vehicle along the travel course, azimuth error of the host vehicle and the other vehicle, and error in a azimuth and/or a curvature radius of the travel course of the host vehicle due to drift of the host vehicle and the other vehicle, by comparing the location of the other vehicle with the location threshold value, and also comparing the azimuth of the other vehicle with the azimuth threshold value. the vehicle location estimation apparatus comprising: an azimuth acquisition device that acquires an azimuth of a direction of travel of the host vehicle; a road radius estimation device (13, 14, 21; 22; 23; 24; 25) that estimates a curvature radius of a road on which the host vehicle is traveling; an other vehicle location acquisition device that acquires the location of another vehicle; and an other vehicle azimuth acquisition device that acquires an azimuth of a travel path direction in which the other vehicle is travelling an azimuth acquisition device that acquires an azimuth of a direction of travel of the host vehicle; a road radius estimation device (13, 14, 21; 22; 23; 24; 25) that estimates a curvature radius of a road on which the host vehicle is traveling; an other vehicle location acquisition device that acquires the location of another vehicle; and an other vehicle azimuth acquisition device that acquires an azimuth of a travel path direction in which the other vehicle is travelling characterized by a determination device (21; 22; 23; 24; 25) that arranges the other vehicle on a coordinate system, an origin of which is a position of the host vehicle, and an axis of which is a travel path direction in which the host vehicle is travelling, and that determines whether or not a road on which the other vehicle is travelling is the same as a road on which the host vehicle is travelling and a travel path direction in which the other vehicle is travelling is the same as the travel path direction in which the host vehicle is travelling, by setting a location threshold value and an azimuth threshold value taking account of a width of a road, error in the acquired location of the other vehicle, error in the estimated curvature radius of the road, change in a curvature of a travel course of the host vehicle along the travel course, azimuth error of the host vehicle and the other vehicle, and error in a azimuth and/or a curvature radius of the travel course of the host vehicle due to drift of the host vehicle and the other vehicle, by comparing the location of the other vehicle with the location threshold value, and also comparing the azimuth of the other vehicle with the azimuth threshold value.