The invention relates to a method for preparing multifunctional three-layer core-shell structure micro/nano particles. The particles are of spherical structures, the thickness of each shell layer is controllable, multiple materials or medicines having different properties can be effectively and independently coated simultaneously, multifunctional characteristic compounding can be realized by adding functional auxiliary materials into each phase, the advantages of multilayer core-shell structures and excellent optical, electrical, magnetic, acoustic and biological characteristics are integrated into a whole, drug controlled release and medical contrast imaging application can be realized, and particularly the core-shell structure has excellent application prospects in the aspects of disease treatment and medical imaging. The preparation method is a coaxial electrostatic spraying method, the process and equipment are simple, the generated particles are controllable in forms, the particle size, shape and core-shell thickness of the obtained core-shell structure particles can be controlled by changing the operating parameters, the particle size is uniform, and the core-shell structure has good application prospects. In addition, the core-shell structure particles can serve as a precursor for preparing a hollow and special ring structure.