In recent years，the eco-environmental risk of microplastics has been widely concerned at home and abroad.Field management measures such as plastic film mulching，organic fertilizer application，irrigation and coated controlled-release fertilizer application resulted in continuous accumulation of microplastics in farmland soil.The migration and transformation of microplastics in soil through physical fragmentation，chemical decomposition and biodegradation may affect soil carbon turnover，and then affect soil carbon storage and carbon-containing gas emission.Therefore，through the summary and arrangement of domestic and foreign literatures，the types and sources of microplastics in farmland soil were systematically combed，and the effects of microplastics on soil plant respiration，enzyme activity and microbial community structure by providing carbon sources were analyzed，then directly or indirectly affected soil carbon emissions and carbon transformation process，including the following aspects: (1)Microplastics are long carbon chain molecular structure，it has impacts on soil organic carbon content and transformation，as well as physical and chemical properties such as soil aggregates，porosity，and water content； (2)The decomposition and carbon turnover of different types of microplastics by fungi and bacteria in soil were different； (3)The microplastics can affect soil carbon conversion by affecting plant growth，changing relative functional gene abundance，enzyme activity and microbial community composition.Based on the analysis of carbon transformation process of microplastics in soil，the paper provides a reference for evaluating the effect of microplastics on soil carbon pool.