-The purpose of this paper was to evaluate the effects of the interference by Urochloa brizantha on coffee seedlings inoculated with arbuscular mycorrhizal fungi. A randomized block design and a 4 x 2 layout was used, where factor A was constituted by seedlings inoculated with Rhizophagus clarus, Claroideoglomus etunicatum and Dentiscutata heterogama, as well as some that were not inoculated, and factor B, constituted by plants in competition or alone. The sowing was conducted on washed sand to produce the coffee seedlings, which, during the matchstick stage, were transplanted into polyethylene bags, and inoculated when showing six pairs of leafs. Then, they were transplanted into pots where they were subjected to interference from two plants of U. brizantha for 90 days, during which time their growth and nutrient accumulation were evaluated on the leaves. As a result, an interaction between the following factors was observed: plant height, leaf area, shoot dry weight, dry weight for roots and P, Mg and Zn content in coffee seedlings. The damaging effect on the growth and P accumulation caused by the weed was reduced in coffee seedlings inoculated with mycorrhiza. Another conclusion was that the inoculation factor increases the competitive power of coffee seedlings. Keywords: Coffea arabica, Rhizophagus clarus, Claroideoglomus etunicatum, Dentiscutata heterogama,Urochloa brizantha. RESUMO -Objetivou-se com este trabalho avaliar os efeitos da interferência de