We present a surface metal grating distributed feedback quantum cascade laser emitting at λ～8.3 μm and operating above 400K in pulsed mode.A very high peak power of 463mW at 290K and still more than 18mW at 400 K is achieved for a high-reflectivity-coated 13-μm-wide and 2.5-mm-long laser.Single-mode emission with a high side mode suppression ratio and wide temperature tuning range is observed.Such a high-power single-mode laser with a simple device process is important for practical applications.