Vacuum insulation panels (VIPs) are high-performance thermal insulation materials that can achieve a reaction-to-fire rating of not lower than Class A (A2). By evacuating the gas within a porous core to a low internal pressure and sealing it with a high-barrier film, VIPs deliver an ultra-low effective thermal conductivity on the order of milliwatts per meter-kelvin, and have been applied in buildings, household appliances, and cold-chain logistics. The barrier film is the critical interface for maintaining the low internal pressure; its properties directly determine the thermal insulation performance and service life of VIPs. This review systematically summarizes the composition and layered architecture, material categories, and key functions of VIP barrier films. Particular emphasis is placed on the mechanisms governing gas and oxygen barrier performance, thermal-bridge effects, and aging resistance. The influences of film structural design and external environmental factors on VIP performance are also analyzed. In addition, recent advances in multifunctional barrier films and their innovative applications are reviewed. Finally, future development directions for VIP barrier films are discussed, aiming to provide insights and reference for the structural design and application-oriented innovation of barrier films.