Biobased degradable materials, which use abundant natural resources such as agriculture, forestry, animal husbandry, marine products, or waste as raw materials, reduce the dependence on nonrenewable resources such as petroleum to a certain extent. Biobased degradable polymers have become alternative materials for many industrial applications to control the risk of environmental damage caused by nonbiodegradable plastics, with the advantages of environmental protection and sustainable development. As representatives of biodegradable polymers, poly(lactic acid) (PLA), polyamides, and polyurethanes all contain heteroatoms. They may degrade easily due to the hydrolysis of ester (–COO–), amide (–CONH–), or ether bonds (–O–). In addition, they have excellent mechanical properties, thermal properties, and barrier properties, and therefore can compete with traditional materials on the market, with a wide range of application prospects. According to statistics, from 2015 to 2023, the scale of China’s biodegradable plastics market grew steadily, reaching 18.9 billion yuan in 2023 (Fig. 7.1) (Industrial Information Network 2020; Ganyi et al. 2022). With the enhancement of people’s environmental awareness and the implementation of the “plastic restriction order”, biodegradable plastics will have a good development prospect. In this chapter, we mainly introduce biobased degradable materials whose monomers come from biomass or are produced by microorganisms, such as PLA, polyhydroxyalkanoates (PHA), polybutylene succinate (PBS), polyamide 4 (PA4) and the second largest natural polymer chitosan (CS), and their applications in packaging, agriculture, and medical and fiber fields.