Abstract: A method of improving grinding, grading and capacity of ores by reducing a fineness content ratio ?0 in settled ores includes providing a two-stage ore grinding and grading system including a first fully closed circuit including a grinder and a hydrocyclone, or a two-stage ore grinding and grading system including a first-stage open circuit, and controlling parameters for ore grinding and grading as follows: controlling a dc an value of a point B on a separation cone of a second-stage ?500 mm hydrocyclone; controlling a fineness content ratio ?0 in settled ores; controlling a second-stage ore grinding and grading load Q2; and acquiring a first-stage grinding, grading and capacity Q of ores.