An optical interferometric measurement apparatus includes an interference optical system to output a monitoring interference signal and a measurement interference signal in accordance with light emitted from a wavelength-swept light source, and a controller to measure a movement of an object to be measured. The controller has a storage to store monitoring data acquired by sampling the monitoring interference signal in each period of the light source and measurement data acquired by sampling the measurement interference signal in each period of the light source and Fourier transformation unit to apply Fourier transform to the measurement data. The controller determines a phase of the measurement interference signal based on the Fourier-transformed measurement data and measures the movement of the object based on the phase.
