The invention provides a nano-colloid fluidic polishing device, which relates to a fluidic polishing device. The invention solves the problems in the prior nano-colloid fluidic polishing process, for example, the nano-colloid is easily polluted; jet energy of the nano-colloid is hard to control; chemical adsorption of free radical-hydroxide radical and workpiece surface atoms is hard to realize; a reversible polymerization decomposition reaction generated between nano-particles in the colloid and the workpiece surface atoms is hard to ensure; and the nano-particles on the workpiece surface and the workpiece surface atoms can not be removed by the action of fluid adherence. In the device, a first flexible seal sack is arranged in a first high-pressure vessel; the lower end of a fourth pipeline is communicated with the upper end of the first flexible seal sack; the upper end of the fourth pipeline is communicated with a first two-position three-way control valve; a sealed nano-colloid vessel is communicated with the first two-position three-way control valve; and a peristaltic pump is arranged on a fifth pipeline. The invention realizes independent circulation of pressure oil and the nano-colloid, controls the jet energy, and removes the nano-particles on the workpiece surface and workpiece surface atoms.