A radar receiver receives reflection wave signals which are a radar transmission signal reflected by a target with plural respective antenna system processors, and estimates an incoming direction of the reflection wave signals. A correlation vector power calculator calculates a correlation vector power based on a correlation vector including outputs of the plural respective antenna system processors. A direction vector correlation calculator calculates a direction vector correlation power on the basis of the correlation vector and a direction vector including information of amplitude and phase deviations that occur between the plural respective antenna system processors for each azimuth angle range of an incoming direction of the reflection wave signals. A distance/azimuth angle detector estimates an azimuth angle of an incoming direction of the refection wave signals based on the correlation vector power and the direction vector correlation power.