This method for estimating the depth of latent scratches in SiC substrates includes an etching step, a measurement step, and an estimation step. In the etching step, a SiC substrate in which at least the surface is formed from single crystal SiC, and which has been subjected to machining, is subjected to heat treatment under Si atmosphere to etch the surface of the SiC substrate. In the measurement step, the surface roughness or the residual stress of the SiC substrate which has been subjected to the etching step is measured. In the estimation step, the depth of latent scratches or the presence or absence of latent scratches in the SiC substrate before the etching step are estimated on the basis of the results obtained in the measurement step.