The present disclosure includes a vehicle state recognition unit configured to determine states of a vehicle using an acceleration value and an angular velocity value, a stopping state gravity vector calculation unit configured to calculate a stopping state gravity vector value, an accelerating state vehicle acceleration vector calculation unit configured to calculate a vehicle acceleration vector value, a vehicle pitch angle vector calculation unit configured to calculate a vehicle pitch angle vector value, and a vehicle pitch angle calculation unit configured to calculate a vehicle pitch angle using a corresponding vehicle pitch angle vector value.