This book explores the flammability characteristics and fire-retardant mechanism of the natural fiber-based composites and biocomposites reinforced with the various fire retardant fillers based on the thermoset, thermoplastic and elastomers. Biocomposites are increasingly viewed as viable alternatives to synthetic fiber-reinforced composites for low- to medium-strength application. However, certain applications may involve the use of such material in elevated temperatures and conditions where the material can be subjected to fire during its service life. Thus, it is essential to understand the thermal decomposition characteristics and fire response of the biocomposites with respect to the type of fiber reinforcements and type of matrix. The book also explores post-fire mechanical properties of the composites. This book is intended for researchers and industrial practitioners who specialize in developing new materials for fire-resistant and low thermal degradation properties.