The invention relates to a nano-emulsion composite, and particularly relates to a nano-composite and a preparation method, and belongs to the field of composite materials. The nano-emulsion compositeincludes a main component and an additive, wherein the main component comprises, by weight, 1-20 parts of ocimum gratissimum oil, 2-10 parts of chrysin, 1-5 parts of grapefruit essential oil, 1-5 parts of wintergreen oil, 1-15 parts of dementholized peppermint oil, 1-5 parts of eucalyptus oil, 1-10 parts of star anise oil, 1-10 parts of spearmint oil, 1-10 parts of geranium oil, and 1-5 parts of betulin. In the nano-emulsion composite, on the basis of the ocimum gratissimum oil, the chrysin is added to remove free radicals, the grapefruit essential oil is added to increasing solubility of different essential oil, the betulin is added for sterilization and antiviral function. Meanwhile, by means of addition of the surfactant, the nano-emulsion composite has anti-inflammation and antiviral functions.