The dependence of photoluminescence spectra of SiGe/Si(001) structures with self-assembled islands on Ge deposition temperature was investigated. Due to inhibition of SiGe alloying and an increase of the Ge content in islands the photoluminescence peak from the islands significantly shifted to low energy with a lowering temperature. The maximum of the peak from the island grown at 600°C was observed at energies less than the energy of the bandgap for bulk Ge. As a result of holes localization in islands the photoluminescence peak from the islands was observed up to room temperature. Sufficient enhancement of the room-temperature intensity of the photoluminescence signal at 1.55 μm was obtained for structures with islands grown on pre-deposited Si1-xGex layer. It is associated with a more effective capturing of holes by densely packed islands in structures with a pre-deposited Si1-xGex layer.