Because of the purpose of determining the species of mushrooms associated with oaks in areas of natural distribution in the Sierra de Pachuca, Hgo., three sites with oaks as an important structural element in the vegetation of the Northwest part of the region were selected. In each site several plots were marked out for observation, where fructiferous bodies from mushrooms were collected and botanical samples of oak species in Quercus mexicana forest (QMF), fir-oak forest (FOF) and Quercus obtusata forest (QOF), since July to November 2002. Subsequently, species of the collected samples were identified. Registered field data was analyzed through value importance (I. V.) and the species association coefficient, besides the consult of specialists and appropriate literature to identify mushrooms species. Six oak species and 37 species of mycorrhizical mushrooms were registered The FOF presented the smallest mycorrhizical mushrooms species number, but it had the best soil fertility characteristics than others. mycorrhizical mushrooms species with greater I. V. were Lactarius thyinos, Inocybe sororia, Russula paludosa, R. xerampelina, Lycoperdum perlatum, Psathyrella spadicea, Russula aff. olivacea and Lactarius croceus. However, Amanita flavoconia, Clitocibe gibba, Inocybe sororia, Lactarius piperatus, Russula emetica, R. densifolia and R. decolorans showed positive coefficients of association with several oak species.