As one of the most promising mid-infrared laser mediums in 3-5 μm wavelength region, Fe2+∶ZnSe crystal has many advantages in material property and conversion efficiency. The absorption characteristic of Fe2+∶ZnSe is investigated. A Fe2+∶ZnSe crystal with size of 10 mm×10 mm×5 mm and Fe2+ doping concentration of 4×1018 cm-3 is excited by a non-chain electric-discharge pulsed HF laser at room temperature. The maximum output energy reaches 65 mJ and the optical to optical conversion efficiency is 31%. The slope efficiency respecting to the absorbed pump energy is 37%.