High quality Pb1-xMnxSe(0≤x≤0.0681) thin films have been grown on BaF2(111) substrates by molecular beam epitaxy. Optical and structural properties of the Pb1-xMnxSe films have been studied using transmission spectrum and high resolution Ｘ-ray diffraction(HRXRD).HRXRD paterns indicate that Pb1-xMnxSe films have cubic-phase structure,and MnSe phase separation is not observed. The film orientation is parallel to (111) surface ofsubstrate. The lattice constant of Pb1-xMnxSe films decreases with increasing Mn content. The Mn content can be obtained by using Vegard's formula. Sharp absorption edges were observed in the transmission spectrum of Pb1-xMnxSe films.The fundamantal band gap of the Pb1-xMnxSe films was obtained by simulation, which increases almost exponentially from 0.28eV at x=0 to 0.49eV at x=0.0681. The refractive index in the wavelength ranged from 4 to 9.5 μm has also been obtained.