Solvent-free flame-retardant enamelled wire silicone resin is disclosed. The enamelled wire silicone resin is prepared by mixing vinyl silicone oil, hydrogen-containing silicone oil, silica and a hydroxy silicone oil treating agent. A preparing method of the enamelled wire silicone resin includes 1) a step of stirring, namely a step of fully mixing the vinyl silicone oil, the silica and hydroxy silicone oil through stirring, and allowing the mixture to stand for 24 h, 2) a step of kneading, namely a step of putting the treated solvent mixture into a kneading machine and kneading, wherein kneading is performed with a cover being opened until the temperature is 175 DEG C, then the cover is covered, vacuumizing is performed, and kneading is performed under vacuum for 2 h, 3) a step of adding low-viscosity vinyl silicone oil, 4) a step of adding the solvent mixture in the step 3) to three-roll grinder and grinding for 6 h, 5) a step of adding into the kneading machine again, kneading, adding the hydrogen-containing silicone oil the weight of which is 0.6 time of the weight of the hydroxy silicone oil, opening the cover, and kneading for 3 h, and 6) a step of adding into the three-roll grinder again and grinding for 2 h. The enamelled wire silicone resin prepared through the method is good in flame retardance, good in insulativity, good in heat resistance and good in tear resistance.