The invention relates to use of quantum dots in a pigment dispersion liquid. The invention also relates to a pigment dispersion liquid, which comprises a pigment, quantum dots, a dispersion agent, a dispersing resin and a solvent. The invention also relates to the process for producing the pigment dispersion liquid. The use of quantum dots provided by the invention broadens the application field of the quantum dots and develops the use thereof in the field of liquid crystal display. The pigment dispersion liquid having quantum dots added therein provided by the invention has a significantly improved stability of dispersion. Furthermore, the quantum dots and the organic pigment can interact with each other by adjusting the composition, the size or the like of the quantum dots, so that the properties of the pigment are improved and the contrast thereof is increased.