An automotive radar having a high level of azimuth accuracy and a broad detectable range by virtue of preventing leaks of unnecessary waves to receiving antennas is to be provided. A transmitting array antenna 1 and receiving array antennas 2a, 2b are arranged on an antenna plate (grounding conductor plate) 3 which serves to ground the antennas, and radio wave absorbers 4 are arranged on two sides of the edges 15 of the antenna plate 3. The radio wave absorbers 4 may be configured of, for instance, a sponge material containing radio wave absorbing grains.