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Vanilla planifolia is attacked by the fungus F. oxysporum f. sp. vanillae. Since there are no resistant genotypes available to producers, they opt for the use of synthetic fungicides to control the disease, however, there is no information on a possible resistance of the pathogen to these commercial fungicides. The goal of the work was to analyze the response of F. oxysporum strains, pathogenic (nine) and non-pathogenic (three) of V. planifolia, to three fungicides of the benzimidazole family and to chlorothalonil, as well as the genetic bases by studying the target proteins of these active ingredients, β-tubulin and GPDH. It was observed that the 12 strains studied were susceptible to the fungicides benomyl and carbendazim, while 11 of them were resistant to thiophanate methyl and nine to chlorothalonil. No relationship was found between the pathogenic character or the origin of the strains and the susceptibility to fungicides. It was found that resistance to thiophanate methyl is not conferred by a point mutation of the β-tubulin coding sequence, as previously hypothesized; apparently, it could be more related to the absence of protein motifs. No relationship was observed between variation in the gene GPDH with the resistance or susceptibility of the strains. [ABSTRACT FROM AUTHOR]