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A greenhouse experiment was conducted to investigate the effects of a root-lesion nematode, #Pratylenchus coffeae#, two arbuscular mycorrhizal (AM) fungi, #Acaulospora mellea# and #Glomus clarum#, and timing of inoculation on the growth and nutrition of a nematode-susceptible Arabica coffee cultivar. The late AM inoculation (added simultaneously with nematodes) did not enhance coffee tolerance to #P. coffeae#. In the presence of #P. coffeae#, late-mycorrhizal plants were P deficient during the entire experiment and their foliar P concentration remained as low as that of non-mycorrhizal plants. After 7.5 months, nematodes decreased AM colonization of late-mycorrhizal plants by half and their biomass was only 20-30% that of the controls. In contrast, early AM inoculation (4 months before nematode inoculation) with either AM species improved the tolerance of coffee to #P. coffeae#. Root colonization by AM was not significantly reduced by #P. coffeae#. Despite higher densities of nematodes, root lesions were less numerous and more localized in early AM inoculated plants than in those of non-mycorrhizal plants. In the presence of #P. coffeae#, early AM-inoculated plants remained P sufficient and their biomass was still 75-80% that of their nematode-free controls. This study shows that in soils with low P levels, enhanced tolerance to #P. coffeae# seems limited to mycorrhizal coffee plants with well established AM symbiosis and improved P status.