There is provided a radar device. A detection vehicle velocity acquiring unit is configured to acquire a detection vehicle velocity detected on the basis of rotation of a wheel. A relative velocity calculating unit is configured to calculate the relative velocity of a still object. A correction value calculating unit is configured to calculate a first correction value on the basis of the detection vehicle velocity and the relative velocity of the still object obtained in a CW mode and calculate a second correction value on the basis of the detection vehicle velocity and the relative velocity of the still object obtained in a FM-CW mode. A vehicle velocity correcting unit is configured to correct the detection vehicle velocity using at least one of the first correction value and the second correction value.