The invention provides a pigment dispersing system and a fabrication method thereof and a colored photoresist. According to the fabrication method of the pigment dispersing system, a polymerizable dyemonomer containing dye molecules in a molecule structure is polymerized around pigment particles to form a colored polymer network by adopting a microemulsion polymerization method, thereby dispersing the pigment particles to fabricate the pigment dispersing system. The target color is achieved through the pigment dispersing system by adopting combined action of the pigment particles and the dyemolecules, so that compared with an existing colored photoresist for achieving the target color only by adopting the pigment particles, the colored photoresist of using the pigment dispersing system has the advantage that the application amount of the pigment particles can be reduced, thereby improving the light transmittance. Furthermore, the dye molecules exist in the colored polymer network, sothat compared with an existing method of directly adding the dye molecules to the colored photoresist, the method of applying the pigment dispersing system to the photoresist has the advantage that the dye molecules have better dispersing stability in the colored photoresist.