Oil-displacing agent as well as preparation method and application thereof

The invention provides an oil-displacing agent as well as a preparation method and application thereof, and belongs to the field of oil extraction in oil fields. The oil-displacing agent provided by the invention comprises a gelatin aqueous solution and silane coupling agent modified SiO2 particles dispersed in the gelatin aqueous solution. According to the invention, the silane coupling agent modified SiO2 particles have oleophylic characteristics; the gelatin aqueous solution has a binding effect on the silane coupling agent modified SiO2 particles and can also be used as a protective layer of the silane coupling agent modified SiO2 particles, so that the contact time of the silane coupling agent modified SiO2 particles and the surrounding environment is shortened to a certain extent, and the consumption of the oil-displacing agent is reduced; when the oil displacement agent is used for oil displacement of an oil field, the oil displacement efficiency is greatly improved on the basis of reducing the consump