An antenna module configured to be attached to a ceiling of a vehicle, the antenna module comprising: an antenna; and a magnetic body, characterized in that the magnetic body includes an upper wall extending longer in a front-rear direction of the vehicle than in a width direction of the vehicle, a pair of walls (32, 32) spaced apart from each other and extending downward from both ends of the upper wall in the width direction, and a groove extending continuously from one end to the other end in the front-rear direction, the groove opens downward and at both sides in the front-rear direction, the antenna is accommodated between the pair of walls (32, 32), wherein the antenna includes a coil spirally wound, the antenna being accommodated between the pair of walls (32, 32) such that an axial direction of the coil intersects a facing direction in which the pair of walls (32, 32) face each other, further comprising: a driver configured to drive the antenna; and a substrate on which the driver is mounted, wherein the substrate is disposed between the pair of walls (32, 32) and is fixed to the magnetic body, and wherein the antenna is electrically connected to and fixed to the substrate, the groove having a cross section of semicircular shape in which a vertex of the semicircular shape is flattened continuously from the one end to the other end in the front-rear direction so that a bottom of the groove is flat, and an inner surface thereof is formed in a curved surface such that the width of the groove decreases toward the bottom of the groove, the substrate being fixed to the bottom of the groove. an antenna; and a magnetic body, characterized in that the magnetic body includes an upper wall extending longer in a front-rear direction of the vehicle than in a width direction of the vehicle, a pair of walls (32, 32) spaced apart from each other and extending downward from both ends of the upper wall in the width direction, and a groove extending continuously from one end to the other end in the front-rear direction, the groove opens downward and at both sides in the front-rear direction, the antenna is accommodated between the pair of walls (32, 32), wherein the antenna includes a coil spirally wound, the antenna being accommodated between the pair of walls (32, 32) such that an axial direction of the coil intersects a facing direction in which the pair of walls (32, 32) face each other, further comprising: a driver configured to drive the antenna; and a substrate on which the driver is mounted, wherein the substrate is disposed between the pair of walls (32, 32) and is fixed to the magnetic body, and wherein the antenna is electrically connected to and fixed to the substrate, the groove having a cross section of semicircular shape in which a vertex of the semicircular shape is flattened continuously from the one end to the other end in the front-rear direction so that a bottom of the groove is flat, and an inner surface thereof is formed in a curved surface such that the width of the groove decreases toward the bottom of the groove, the substrate being fixed to the bottom of the groove. a driver configured to drive the antenna; and a substrate on which the driver is mounted, wherein the substrate is disposed between the pair of walls (32, 32) and is fixed to the magnetic body, and wherein the antenna is electrically connected to and fixed to the substrate, the groove having a cross section of semicircular shape in which a vertex of the semicircular shape is flattened continuously from the one end to the other end in the front-rear direction so that a bottom of the groove is flat, and an inner surface thereof is formed in a curved surface such that the width of the groove decreases toward the bottom of the groove, the substrate being fixed to the bottom of the groove.