this work aimed to evaluate the chemical composition, yield, and antifungal activity of the essential oils (eo) of native species from the 'campos de cima da serra' region, south brazil. the species aloysia gratissima, aloysia lycioides, blepharocalyx salicifolius, cunila angustifolia, myrciaria delicatula, myrcia brasiliensis, ocimum sp., and schinus polygama had an eo yield higher than 0.1% v/m. the in vitro antifungal activity of these oils was tested on the fungi alternaria alternata, fusarium oxysporum, botrytis cinerea, sclerotinia sclerotiorum, and colletotrichum gloeosporioides, with an eo concentration of 0.1% v/v. chemically, the eo of ocimum sp. presented the highest dissimilarity compared to other species; the eos of m. delicatula and m. brasiliensis presented the highest degree of similarity. ocimum sp. eo inhibited the growth of all fungi; the eo of b. salicifolius had no inhibitory effect. the remaining oils had an intermediate antifungal activity which also depended on the fungi species.