The invention discloses a preparation method of water-based flexible bending-resistant carbon-based high-conductivity ink, and the method comprises the following steps: adding carbon-based particles ball-milled by a plasma ball mill as a conductive filler, a binder, an auxiliary agent and the like into an aqueous solvent, and uniformly dispersing through ultrasound to finally obtain the water-based flexible bending-resistant carbon-based high-conductivity ink. After the conductive ink prepared by the method is cured at normal temperature, the conductivity of a printed circuit (with the film thickness of 30mu m) can reach 3.3*10<2>S/m, the printed circuit can be bent repeatedly for a long time with a large load, and the conductivity of the printed circuit can be reduced by no more than 1.0%after 10,000 times of bending.