Thermal analysis of polychloroprene elastomer composites was carried out. Addition of reinforcing fillers such as precipitated silica (Vulcasil-S), carbon black (FEF N-550), and short silk fiber led to significant changes in the degradation pattern, depending on their reinforcement and adhesion ability with the elastomer matrix. Attempts were made to correlate the variations of thermal properties with the surface chemistry and the reinforcement characteristics of these fillers.