A detailed investigation of the dependence of the photoluminescence from porous silicon carbide on preparation conditions and starting material is presented. Porous silicon carbide prepared from different polytypes shows almost identical emission spectra, demonstrating a clear impedance of the band‐gap energy of a particular SiC polytype. Emission bands with peak energies of 2.43, 2.22, 2.07, and 1.93 eV were resolved with the use of selective excitation by tuning the excitation wavelength. The origin of luminescence is suggested to relate to defect states produced at the etched surface. ©1995 American Institute of Physics.