The invention discloses a fabrication process for a liquid metal filtering RT coil. The fabrication method comprises the following steps of A, winding the RT coil; C, completely wrapping the wound RT coil with liquid metal so that a metal layer is formed on the RT coil to obtain a filtering component; D, encapsulating a waterproof organic material on the filtering component to obtain an encapsulation component; and E, naturally drying or manually drying the encapsulation component to obtain the liquid metal filtering RT coil. The filtering component is obtained by winding and matching of the liquid metal and has filtering efficiency; and the encapsulation component is obtained by encapsulating the filtering component with the waterproof organic material, so that the encapsulation component has waterproof performance. The fabrication process is simple in step, the fabricated product has an electron filtering function, and the harmonics is substantially reduced; moreover, the product fabricated according to the process is simple in circuit and part and is economic and practical; and since there are not many LC filtering designs on the circuit, the problems of space and power consumption and the like of the circuit are greatly reduced.