A rectifier of an alternator according to the present invention includes: a first heat sink; first unidirectional conducting element bodies that are disposed on a front surface of the first heat sink so as to be spaced apart; a second heat sink that is disposed so as to be separated from the first heat sink; second unidirectional conducting element bodies that are disposed on a front surface of the second heat sink so as to be spaced apart; and a circuit board that has a circuit board terminal by which the first unidirectional conducting element bodies and the second unidirectional conducting element bodies are connected so as to constitute a bridge circuit, and a terminal connection portion is configured by respectively connecting first terminals of the first unidirectional conducting element bodies and second terminals of the second unidirectional conducting element bodies adjacently in a common plane with the circuit board terminal. Thus, connection workability between the first terminals of first unidirectional conducting element bodies and the circuit board terminal and between the second terminals of second unidirectional conducting element bodies and the circuit board terminal is improved.