The use of mid-IR fiberoptic components in spectroscopy and analysis using A4B6 tunable diode lasers has been studied, and the results are reported. Spectral parameters of the fibers and complete spectroscopic systems based on the fibers and Pb-salt diode lasers are presented. The further development of the presented systems for applications in remote monitoring, multicomponent gas mixtures analysis, and evanescent wave spectroscopy of gases is addressed.