We present a high-power mid-infrared single-frequency pulsed fiber laser (SFPFL) with a tunable wavelength range from 2712.3 to 2793.2 nm. The single-frequency operation is achieved through a compound cavity design that incorporates a Germanium (Ge) etalon and a diffraction grating, resulting in an exceptionally narrow seed linewidth of ~780 kHz. Employing a Master Oscillator Power Amplifier (MOPA) configuration, we attain a maximum average output power of 2.6 W at 2789.4 nm, with a pulse repetition rate of 173 kHz, a pulse energy of 15 μJ, and narrow linewidth of ~850 kHz. This achievement underscores the potential of the mid-infrared SFPFL system for applications requiring high coherence and high power, such as high-resolution molecular spectroscopy, precision chemical identification, and nonlinear frequency conversion.