Ageratina adenophora is one of the worst invasive weeds in China, which has brought economical and ecological lost, but no effectual measurements have been applied to avoid its invasion and spreading. To control the damage on local vegetation and native habitats after the invasion by this exotic weed, a better understanding of its invasion mechanism is urgently required. It is well-known that arbuscular mycorrhizal fungi (AMF) play important roles in ecosystem functioning, and this is considered as a reason for the success or failure of plant invasion. However, few studies are considered which AMF species could affect plant invasion, and which plant species' invasiveness could be affected, and what the roles of AMF in the interaction between exotic plant and native species, and how AMF can affect the invasion process are largely unknown. Therefore, studies of the role of AMF species in mediating the invasions of exotic plants and the influence of such mutualisms on plant competition could provide better understanding of the mechanisms of exotic plant invasion. In previous studies we showed that soil microbial community including AMF was changed after the invasion of A. adenophora, and such changes might be significant for its further invasion and spreading. However, studies on how the A. adenophora invasion could affect AMF community and how the affected AMF community could feedback to further invasion are needed. As a result, in this paper we first investigated the effect of A. adenophora invasion on the rhizosphere soil physical and chemical characters, and then root AMF colonization rate and AMF community structure under three plant communities (native weeds, a mixed community of A. adenophora and native plants, and a A. adenophora dominated community). All three plant communities were within the A. adenophora invaded area, where the plant community is transiting gradually from the dominated native plants to a single species of A. adenophora. Our results demonstrated that the A. adenophora invasion decreased soil pH, increased soil organic carbon, total nitrogen and available potassium by 83%, 107%, and 111%, respectively, but no changes in total phosphorus. However, the organic phosphorus showed an increase trend, while available phosphorus a decrease trend along with the transition of plant community from the dominated native plants to A. adenophora dominated. The colonization of AMF of native weeds was restrained by A. adenophora invasion. A. adenophora invasion changed the structure of AMF community from Acauospora dilatata dominated AMF community to Glomus claroideum dominated AMF community along with the aggravation of the invasion. Meanwhile, A. adenophora accumulated G. claroideum selectively occurred, while other AMF species especially A. dilatata was restrained in the rhizosphere. The cluster analysis for the AMF species based on their abundance showed that, AMF community in the soil of A. adenophora dominated area was different from that of the native plants as well as that of the native weeds growing with A. adenophora interspersed. Changes of soil physical and chemical characters, AMF colonization and AMF community might play an important role in the A. adenophora invasion and its further spreading.