The invention discloses a preparation method of a super wetting titanium dioxide nanorod porous membrane and application of the super wetting titanium dioxide nanorod porous membrane to emulsion separation, and belongs to the technical field of function materials. The method comprises the following steps: preparing a PVP/TiO2 composite fiber membrane through an electrospinning technology, and drying the composite fiber membrane in a drying oven; laying the dried composite fiber membrane in a muffle furnace for calcining the composite fiber membrane for a certain period, removing organic carbon in the composite fiber membrane, calcining the composite fiber membrane to form an inorganic TiO2 fiber membrane, vertically laying the calcined inorganic TiO2 fiber membrane into a hydrothermal polymeric pecursor solution in a polytetrafluoroethylene liner, and performing a hydrothermal reaction, so as to obtain a super-hydrophilicity and underwater super-oleophobicity porous super wetting micro-nano composite structure membrane. The obtained membrane has high environmental stability, namely acid resistance, alkali resistance and salt resistance, and can be applied to sewage treatment in harsh acid and alkali salt environments, so that the efficient separation of a corrosive emulsion is realized, and e the application value is high. The preparation method is simple, and is convenient, efficient and rapid for emulsion separation.