Abstract: Due to the widely use of plastic products， an increasing number of micro-nano plastics （MNPs） particles are released into the environment， and which become a global environmental problem. MNPs can enter the human body through the different routes， and which harm human health. The potential health risks caused by MNPs have gradually become a research hotspot. There have been numerous research reports on the detection of MNPs in different tissues of the human body and their potential harm to the different organs and systems. In the report， the research results of microplastics during recent years were retrieved， the exposure pathways of MNPs entering the human body were summarized， the effects and possible mechanisms of MNPs on animal metabolic system from different levels were reviewed， and the future research focus and direction were discussed.