The invention relates to a signal processing method for optical fiber distribution measurement, using an optical fiber distribution measurement system (100), the method comprising: with use of two kinds of signals that are an elastic wave measurement signal obtained by analyzing a phase shift of Rayleigh scattering light measured in a measurement time of 1 millisecond or less, and a temperature-strain distribution measurement signal obtained by analyzing a frequency shift of Rayleigh scattering light measured in a measurement time of 30 seconds or more by tunable wavelength coherent optical time domain reflectometry, calculating the phase error from the temperature-strain distribution measurement signal, and correcting the elastic wave measurement signal by the phase error.