The root microbiome refers to the community of microbes living in association with a plant\'s roots,and includes mutualists,pathogens,and commensals.Here we focus on recent advances in the study of root commensal community which is the major research object of microbiome-related researches.With the rapid development of new technologies,plant-commensal inter-actions can be explored with unprecedented breadth and depth.Both the soil environment and the host plant drive commensal community as-sembly.The bulk soil is the seed bank of potential commensals,and plants use root exudates and immune responses to build healthy microbial communities from the available microbes.The plant microbiome extends the functional system of plants by participating in a variety of proc-esses,including nutrient absorption,growth promotion,and resistance to biotic and abiotic stresses.Plants and their microbiomes have evolved adaptation strategies over time.How-ever,there is still a huge gap in our under-standing of the regulatory mechanisms of plant-commensal interactions.In this review,we sum-marize recent research on the assembly of root microbial communities and the effects of these communities on plant growth and development,and look at the prospects for promoting sus-tainable agricultural development through the study of the root microbiome.