PURPOSE: To enable detection accuracy of a slip angle of a vehicle to be detected to be improved by preventing a reception frequency of one transmitter/ receiver from being affected by that of the other transmitter/receiver in a doppler-type vehicle slip angle detection device with two transmitters/receivers which are provided with transmission and reception portions.

CONSTITUTION: A transmission portion 20 and a reception portion 24 are provided for detecting a vehicle in forward and backward directions and a transmission portion 22 and a reception portion 26 are provided for detecting a vehicle in left and right directions. Then, after transmission of the transmission part 20 and reception at the reception part 24, a speed of the vehicle in forward and backward directions is detected and then a speed of the vehicle in left and right directions is detected after transmission of the transmission portion 22 and reception of the reception portion 26. Then, a vehicle slip angle is calculated based on the speed of the vehicle in forward and backward directions and the speed of the vehicle in left and right directions.