Biodegradation is a decomposition process of organic material with the help of micro-organisms (bacteria, algae, fungi etc.) which results in residues in the form of water, CO2 and/or methane which are non-toxic for the environment.

The ability of a polymer to biodegrade depends on its chemical structure and is not related to the resource used for its manufacture. A polymer derived from fossil resources may in this way be biodegradable.