Abstract: Mid-infrared (MIR, 2–5 μm) fiber laser technology has attracted increasing attention due to its unique advantages in molecular spectroscopy, biomedical applications, advanced manufacturing, and defense. The development of high-performance all-fiber MIR laser systems strongly relies on reliable passive fiber devices, particularly fiber combiners and fiber Bragg gratings (FBGs) based on fluoride glass fibers. This review systematically summarizes the recent progress of MIR fluoride fiber-based combiners and FBGs from the perspectives of material properties, fabrication techniques, device performance, and system integration. The intrinsic advantages of fluoride glasses, including low phonon energy and broad transmission window, are discussed alongside their limitations in thermal stability and environmental durability. Various combiner configurations and grating inscription methods are systematically compared in terms of coupling efficiency, spectral characteristics, and power handling capability, with femtosecond laser direct writing and phase mask techniques representing the main approaches for FBG fabrication. Current challenges, including fabrication complexity, limited repeatability, insufficient power tolerance, and difficulties in low-loss integration, are analyzed. Finally, future development directions toward improved material engineering, fabrication standardization, and device integration are outlined, aiming to promote the transition of MIR fiber devices from laboratory research to practical applications.