An antenna module configured to be attached to a ceiling (R) 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 (Y) of the vehicle than in a width direction (X) of the vehicle , a pair of walls spaced apart from each other and extending downward from both ends of the upper wall in the width direction (X), and a groove extending continuously from one end to the other end in the front-rear direction (Y), the groove opens downward and at both sides in the front-rear direction (Y), the antenna is accommodated between the pair of walls , wherein the antenna includes a coil spirally wound, the antenna being accommodated between the pair of walls such that an axial direction of the coil intersects a facing direction (X) in which the pair of walls 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 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 (Y) 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 (Y) of the vehicle than in a width direction (X) of the vehicle , a pair of walls spaced apart from each other and extending downward from both ends of the upper wall in the width direction (X), and a groove extending continuously from one end to the other end in the front-rear direction (Y), the groove opens downward and at both sides in the front-rear direction (Y), the antenna is accommodated between the pair of walls , wherein the antenna includes a coil spirally wound, the antenna being accommodated between the pair of walls such that an axial direction of the coil intersects a facing direction (X) in which the pair of walls 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 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 (Y) 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 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 (Y) 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 . <EOS>