Single crystals of pure and Er3+ doped BaLaGa3O7 were grown successfully by the Czochralski technique. The absorption spectra, emission spectra including up-conversion, near-infrared and mid-infrared fluorescence spectra, as well as the fluorescence decay curves were measured at room temperature. The optical parameters of absorption and emission cross sections, the fluorescence lifetimes were evaluated and compared. Based on the Judde-Ofelt theory, Judde-Ofelt parameters such as the fluorescent branching ratios, the spontaneous transition probabilities and the radiative lifetimes were calculated. According to the energy transfer diagram, the rate equation model was built and discussed. In summary, Er3+: BaLaGa3O7 crystal is attractive and significant as laser gain material for realization of similar to 2.7 mu m laser output.