To provide a technique capable of accurately obtaining the attitude of a vehicle in the pitch direction. A control device for a vehicular lamp which controls the optical axis of a vehicular lamp in accordance with an attitude change in pitch direction of the vehicle is disclosed. The device includes an angle calculation part which obtains a first and a second acceleration by eliminating the gravitational acceleration component from each acceleration in the vertical and the longitudinal direction of the vehicle, calculates a vehicle traveling direction acceleration based on the accelerations, and obtains a vehicle attitude angle based on the correlation between the vehicle traveling direction acceleration and the first and the second accelerations. The angle calculation part obtains the attitude angle of the vehicle when it determines that the vehicle is accelerating or decelerating based on the determination on the basis of each acceleration difference at the predetermined time.