An optical interference measuring apparatus comprising: a measuring unit configured to acquire an interferogram of an interference wave by irradiating a measurement target and a reference surface with electromagnetic waves and causing a reflected wave from a reflecting surface of the measurement target to interfere with a reflected wave from the reference surface; and a signal processing unit configured to configure an intensity profile in a depth direction by performing Fourier transform of the interferogram, the signal processing unit including a model parameter estimation unit configured to estimate, based on a model formula of an interferogram when it is assumed that a measurement target is a layered structure having at least one reflecting surface, a parameter for the model formula for each assumed surface count, an optimal model selection unit configured to select an optimal model formula by a statistical technique from the model formula to which a parameter estimated for each of the assumed surface count is applied, and an intensity profile reconfiguration unit configured to reconfigure an intensity profile in the depth direction based on the optimal model formula, characterized in that the model parameter estimation unit estimates the parameter for the model formula for each assumed surface count in a predetermined assumed surface count range, and the optimal model selection unit reconfigures an interferogram by using the model formula to which a parameter estimated for each of the assumed surface count is applied, calculates a likelihood between the reconfigured interferogram and an original interferogram, and selects an optimal model formula based on an information amount criterion obtained by setting the assumed reflecting surface count as the degree of freedom. a measuring unit configured to acquire an interferogram of an interference wave by irradiating a measurement target and a reference surface with electromagnetic waves and causing a reflected wave from a reflecting surface of the measurement target to interfere with a reflected wave from the reference surface; and a signal processing unit configured to configure an intensity profile in a depth direction by performing Fourier transform of the interferogram, the signal processing unit including a model parameter estimation unit configured to estimate, based on a model formula of an interferogram when it is assumed that a measurement target is a layered structure having at least one reflecting surface, a parameter for the model formula for each assumed surface count, an optimal model selection unit configured to select an optimal model formula by a statistical technique from the model formula to which a parameter estimated for each of the assumed surface count is applied, and an intensity profile reconfiguration unit configured to reconfigure an intensity profile in the depth direction based on the optimal model formula, characterized in that the model parameter estimation unit estimates the parameter for the model formula for each assumed surface count in a predetermined assumed surface count range, and the optimal model selection unit reconfigures an interferogram by using the model formula to which a parameter estimated for each of the assumed surface count is applied, calculates a likelihood between the reconfigured interferogram and an original interferogram, and selects an optimal model formula based on an information amount criterion obtained by setting the assumed reflecting surface count as the degree of freedom. <EOS>