A Cr∶ZnS main oscillation power amplifier (MOPA) laser experimental setup was designed and constructed. The oscillator adopted a four mirror folded cavity structure and achieved a continuous laser output with a power of 350 mW and a central wavelength of 2393 nm at a pump power of 3.4 W. By using a reflective grating, a tunable laser was obtained with a tuning range of 550 nm from 2075 nm to 2625 nm. The spectral full width at half maximum was 1.2 nm at the peak wavelength of 2450 nm. The oscillator was used as a seed source, the amplification characteristics of domestically produced Cr∶ZnS crystals with different doping concentrations were experimentally studied and contrastive analysis. Among them, the Cr∶ZnS crystal with the absorption coefficient of 3.3 cm^-1 and the crystal dimensions of 2 mm×4 mm×8 mm exhibited the best gain output, achieving an amplification factor of 3.3. By using a two-stage amplifier, the small-signal tunable seed source was amplified. A maximum output power of 51.7 mW was achieved with a central wavelength of 2275 nm.