In the case of biodegradable polymerBiodegradable polymer blend nanocomposite, it is important to understand how each component of the blend, the attributes of the filler particles (such as composition, shape, and size), and their placement affect the composite degradabilityDegradability. By understanding these elements, we can gain insights into how to adjust the degradationDegradation rate to achieve a balance between durabilityDurabilityand degradabilityDegradability in line with product specifications. This chapter reports the overview of biodegradabilityBiodegradability of various polymer blendPolymer blendnanocompositesPolymer blend nanocomposites and the factors that influence their biodegradabilityBiodegradability.