The antifungal therapy combined is used in clinical practice of several mycoses as it may increase the efficacy of the treatment. The use of natural products (phytochemicals) in combination with conventional antifungal drugs has been related to beneficial effects, mainly synergistic effects. The aim of this study was to evaluate the effect of the combined use of eugenol / isoeugenol, compounds with recognized antimicrobial activity, in association with antifungal amphotericin B against strains of Cryptococcus neoformans. The combined antifungal effect were be determined from the Fraction Inhibitory Concentration index - checkerboard technique. The results obtained in this study showed that eugenol in combination with amphotericin B had antagonistic effect against the strains of C. neoformans, LM 615 and INCQS 40221 (FIC index 6.0 and 4.0), respectively. The combination of the isoeugenol and amphotericin B also showed antagonistic effects for both the LM 615 strain and INCQS 40221 (FIC index 6.0 and 5.0), respectively. This study contributed to the understanding of the antifungal effects of the association of phenylpropanoids (eugenol / isoeugenol) with amphotericin B. Further studies are needed to evaluate and compare the effects of the association of these phytochemicals with other conventional antifungal drugs used against C. neoformans.