Abstract: The invention encompasses biodegradable compositions (e.g., biodegradable plastics) and methods of preparation and use thereof, and disposable products made from the claimed compositions. Raw materials for preparing the biodegradable plastic include one or more polymers and thermoplastic starch, fiber, starch, a plasticizer, and a coupling agent. The biodegradable composition has the advantages of short degradation cycle, good mechanical properties, and a low manufacturing cost.