PbSe/PbSrSe multiple-quantum-well (MQW) structures and PbSrSe thin films were grown on BaF2 (111) substrates by molecular beam epitaxy (MBE) and characterized by Fourier transform infrared (FTIR) spectrometer. Strong photoluminescence without Fabry-Perot interference fringes was observed even at room temperature from the MQW structures. The peak energies for the MQW structures with different well widths shifted to high energy with increasing temperature. The absorption edge of PbSrSe layer was determined by transmission spectra. Meanwhile, we designed and fabricated λ=4.1 μm MQW vertical cavity surface emitting laser (VCSEL). A power output of 40 mW was obtained at room temperature. The room temperature threshold pump density is 200 kW/cm2.