In this study, the latest research results of droplet microfluidics, membrane emulsification, and coaxial electrospray preparation of double emulsion are introduced, and their advantages and disadvantages are compared and analyzed. The limitation of microfluidic prepared double emulsion industrialization and its related research was pointed out. The latest research results of double emulsion in the fields of food, cosmetics, and biomedicine were reviewed, and the advantages and prospects of double emulsion applications prospected.