This study aimed to analyze the phytochemical profile and drying with prediction of the leaves of Ocimum citriodurum L., quantify the total phenolics and flavonoids and determine the unprecedented potential of the fungicidal activity of the oil-in-water nanoemulsion incorporated with essential oil and extract hydroalcoholic of O. citriodurum L.The results obtained for fungicidal action attested to a CIM a strong inhibition for the action of essential oils and hydroalcoholic extracts with a concentration of 250 µg mL-1 in front of A. niger, C. gloeosporioides and P.chrysogenum. CFM's of 300, 250 and 500 mL-1 were observed in front of A. niger, C. gloeosporioides and P. chrysogenum, respectively. With the results obtained it is stated that a stable nanoemulsion was obtained for both (EX) and (OE) and that they present active compounds in which they favor an excellent antifungal activity.