A tire monitoring device may be used in conjunction with a tire monitoring system for a vehicle. The tire monitoring device includes a tire monitoring sensor unit having a state monitoring sensor monitoring a tire state, such as a tire pressure, and a first acceleration sensor and a second acceleration sensor respectively measuring accelerations in first and second directions on a plane perpendicular to a wheel axis, and a controller. The controller is configured to determine whether a wheel is on the left or right side of the vehicle on the basis of a relationship between alternating signals of the first acceleration sensor and the second acceleration sensor and determining whether or not a tire event has occurred with reference to a calculated value based on the accelerations measured by the first acceleration sensor and the second acceleration sensor. The tire monitoring device performs minimum operation required for automatic tire location recognition, thereby minimizing battery consumption and reducing the calculation load of the tire monitoring device itself and a central control unit.