The invention belongs to the field of veterinary medicines, and particularly discloses oil-in-water type Febantel nanoemulsion and a method for preparing the same. The oil-in-water type Febantel nanoemulsion comprises, by weight, 1-20% of Febantel, 25-45% of surfactant, 0-20% of co-surfactant, 1-20% of oil and the balance water. The surfactant is EL40, the co-surfactant is absolute ethyl alcohol,and the oil is fatty glyceride. The oil-in-water type Febantel nanoemulsion and the method have the advantages that the oil-in-water type Febantel nanoemulsion is uniformly distributed and is low in surface tension, excellent in flowability and convenient to administer, and systems are transparent and are good in stability; the oil-in-water type Febantel nanoemulsion can be quickly swallowed by reticuloendothelial cells after being administrated, accordingly, effects of medicines can be quickly realized, constant blood concentration and pharmacological effects can be maintained, the bioavailability of the medicines can be improved, the efficacy can be enhanced, and the dosage and use frequencies of the medicines can be reduced.