The invention discloses a stone production three-section screening and grading system and a production method. The stone production three-section screening and grading system comprises a feeding beltconveyor, a first distributor, a primary vibration screen, a return pre-screening chute, pre-screening electro-hydraulic three-way chutes of various particle sizes, undersize funnels of various particle sizes, a return belt conveyor, a 45-80mm finished product belt conveyor, a sand making belt conveyor, a 0-30mm belt conveyor, a second distributor, a secondary vibration screen, a 10-30mm finishedproduct belt conveyor, a 0-10mm belt conveyor, a third distributor, a ternary vibration screen, a 3-10mm pre-screening electro-hydraulic three-way chute, a 0-10mm finished product belt conveyor, a sand making feeding bucket lifter, a sand making buffer bin and a lifter chute. The three-section stone production screening and grading system is adopted, the performance of the vibration screens can beachieved fully, the screening efficiency, production capacity and stone quality can be improved, production dispatching management is facilitated, modular design of the screening system is facilitated, and bases are provided for standard construction of the stone production screening system.