Luminescence studies have been performed on phosphorus-doped diamond films deposited by hot-filament chem. vapor deposition. A broad luminescence band, centered around 1.9 eV, is revealed in the cathodo luminescence spectra of homoepitaxial and polycryst. films, whereas the blue band-A luminescence, which is characteristic for undoped diamond, is quenched in the presence of phosphorus. The 1.9 eV luminescence band could not be excited by Ar+ laser light (2.54 eV) and did not show a zero-phonon line in the spectrum. Therefore, we suggest that this band is a red form of band-A luminescence, related to electron-hole recombination at substitutional phosphorus and a phosphorus-vacancy complex