A measurement apparatus that measures, as an error under measurement, at least one of a gain error and a phase error of a quadrature demodulator or a quadrature modulator as a measurement target. The measurement apparatus includes an output control section that causes the measurement target to output a signal, a detecting section that detects a measured signal representing a real component and an imaginary component of the signal output from the measurement target, and a calculating section that calculates, as the gain error or the phase error, a solution for a variable that maximizes a correlation value between the measured signal detected by the detecting section and an ideal signal that includes the error under measurement as the variable and that represents the measured signal that should be output by the measurement target.