The invention relates to the field of coupling of power plant power generation and clean coal production, and discloses a method and a system for coupling power plant power generation and clean coal production. The method comprises: (1) directly heating raw coal by using first flue channel gas with a temperature of 800-1200 DEG C from a power plant boiler, and carrying out coal conversion to obtain first raw gas and converted coal, wherein the final conversion temperature of the coal conversion is 500-640 DEG C, and the conversion time is 10-60 min; (2) directly heating the converted coal by using second flue channel gas with a temperature of 800-1200 DEG C from the power plant boiler, and carrying out coal impurity removing to obtain second raw gas and impurity removed coal, wherein the final impurity removing temperature of the coal impurity removing is 650-750 DEG C, and the impurity removing time is 10-60 min; (3) returning the first raw gas and the second raw gas to the power plant in the form of return air so as to be used for power generation; and (4) carrying out dry cooling on the impurity removed coal to obtain clean coal. With the method and the system of the present invention, the normal power generation of the power plant is achieved while the low-grade raw coal is produced into the clean coal so as to reduce the pollutant emission in the clean coal production andthe subsequent utilization process.