The work shows the research related to the degradation behaviour of PLA for food contact and the migration of its chemical substances. The work aims to provide information for the safety and environmental protection of polylactic acid (PLA) for food contact and the improvement of relevant laws and regulations. In addition in the work, the characteristics of PLA, the migration of heavy metals, additives and oligomers in PLA for food contact, and the degradation of PLA together with its composites are analyzed and summarized. Results show that PLA not only bears the same potential safety hazards as traditional plastics, but also has the safety problems caused by the migration of self-degradation products. The degradability of PLA is affected by a variety of factors, not only by its own properties, but also by the properties of copolymers. Conclusions could be drawn that there are still many challenges in the utilization of PLA for food contact. With the increasingly extensive application of PLA for food contact, it is necessary to carry out in-depth research on its safety and environmental protection.