An angle detection device, comprising: a three-phase resolver configured to output rotating positional information of a rotating body, as an electrical signal, the three-phase resolver being configured to output a three-phase resolver signal including a resolver signal of phase A changing depending on a turning angle of a rotation body, a resolver signal of phase B, which is different in phase by 120 degrees from the resolver signal of phase A, and a resolver signal of phase C, which is different in phase by 120 degrees from the resolver signal of phase B, when an excitation signal is given to the three-phase resolver; a sine wave generator configured to generate a sine wave signal; a direct current voltage generator configured to generate a direct current voltage; an abnormality determination controller configured to output a switch signal S1 = 1, while an abnormality determination process of determining an abnormality of the three-phase resolver is being performed, and to output the switch signal S1 = 0 in any other case; an excitation signal supplier configured to switch between the sine wave signal generated by the sine wave generator and the direct current voltage generated by the direct current voltage generator in response to the switch signal S1 from the abnormality determination controller, and to supply the selected one to the three-phase resolver as an excitation signal; a voltage measurement portion configured to measure output voltages of phases of the three-phase resolver signal output from the three-phase resolver; and an abnormality detector configured to detect an abnormality of the three-phase resolver, by comparing the output voltages of the phases of the three-phase resolver measured by the voltage measurement portion, when the excitation signal supplier supplies the direct current voltage generated by the direct current voltage generator, as the excitation signal, wherein the excitation signal supplier is configured to select and output the sine wave signal from the sine wave generator when the switch signal S1 = 0, and to select and output the direct current voltage from the direct current voltage generator when the switch signal S1 = 1, and the abnormality detector is configured to determine that the three-phase resolver is in a normal state when the output voltages of phases of the three-phase resolver signal are all equal, and to determine that the three-phase resolver is in an abnormal state when all output voltages of phases of the three-phase resolver signal do not have equal potentials. a three-phase resolver configured to output rotating positional information of a rotating body, as an electrical signal, the three-phase resolver being configured to output a three-phase resolver signal including a resolver signal of phase A changing depending on a turning angle of a rotation body, a resolver signal of phase B, which is different in phase by 120 degrees from the resolver signal of phase A, and a resolver signal of phase C, which is different in phase by 120 degrees from the resolver signal of phase B, when an excitation signal is given to the three-phase resolver; a sine wave generator configured to generate a sine wave signal; a direct current voltage generator configured to generate a direct current voltage; an abnormality determination controller configured to output a switch signal S1 = 1, while an abnormality determination process of determining an abnormality of the three-phase resolver is being performed, and to output the switch signal S1 = 0 in any other case; an excitation signal supplier configured to switch between the sine wave signal generated by the sine wave generator and the direct current voltage generated by the direct current voltage generator in response to the switch signal S1 from the abnormality determination controller, and to supply the selected one to the three-phase resolver as an excitation signal; a voltage measurement portion configured to measure output voltages of phases of the three-phase resolver signal output from the three-phase resolver; and an abnormality detector configured to detect an abnormality of the three-phase resolver, by comparing the output voltages of the phases of the three-phase resolver measured by the voltage measurement portion, when the excitation signal supplier supplies the direct current voltage generated by the direct current voltage generator, as the excitation signal, wherein the excitation signal supplier is configured to select and output the sine wave signal from the sine wave generator when the switch signal S1 = 0, and to select and output the direct current voltage from the direct current voltage generator when the switch signal S1 = 1, and the abnormality detector is configured to determine that the three-phase resolver is in a normal state when the output voltages of phases of the three-phase resolver signal are all equal, and to determine that the three-phase resolver is in an abnormal state when all output voltages of phases of the three-phase resolver signal do not have equal potentials.