Optical properties of nearly stoichiometric GaAs epilayers and GaAs/AlAs multiple quantum wells which were grown by molecular beam epitaxy at low temperatures were studied by utilizing photoluminescence measurements. Bright near-band edge emissions are observed from these low-temperature grown structures. GaAs epilayers exhibit strong carbon acceptor related emission and weak exciton related emission. The intensities of these near-band edge emissions are found to bit highly dependent on the As;Gn flux ratio utilized for the growth. The low-temperature grown multiple quantum wells exhibit strong emission at 4.5 K whose intensities are comparable to those of multiple quantum wells grown at normal high temperatures. The emissions of the low-temperature grown samples are observed even at room temperature indicating effective confinement of excitons in the wells, but their intensities become weaker than those of the high-temperature grown samples by two order of magnitudes.