Single-crystal PbTiO3 layers were grown on (001) SrTiO 3 substrates by molecular beam epitaxy using hydrogen peroxide as an oxidant. Phase composition and structural properties of the films were examined as a function of growth parameters. It was found that single-phase PbTiO 3 films grew epitaxially at substrate temperatures of 600°C and higher, whereas layers grown at lower temperature contained PbO inclusions. The epitaxial relationship between the films and the substrates was (001)PbTiO 3//(001 )SrTiO3 and PbTiO3//SrTiO 3. No evidence of a-domains was found. Full widths at half maximum of (001) PbTiO3 rocking curves were as low as 6-8 arcmin for 50-60 nm thick films, indicating high crystal quality of the films. From ellipsometric measurements, refractive index and band gap of PbTiO3 were found to be 2.66 at 633 nm and 3.8 eV, respectively.