The invention provides a crushing and automatic conveying system and method of a natural rubber, which belongs to the field of a tire preparation technology. The system is characterized in that a natural rubber block is loaded into a rubber frame by a robot and is conveyed to a to-be-fed hole after being detected without error automatically by a metal detector on a conveying belt; the natural rubber block enters into a crusher from the to-be-fed hole and is crushed into rubber particles, and then the rubber is automatically discharged; the rubber particles automatically enter into a blending tank through conveying of the conveying belt; the rubber particles are conveyed by the conveying belt to a crushed rubber particles storing tank; an automatic weighing system is arranged at the crushed rubber particles storing tank; the crushed rubber particles are discharged to a to-be-blanked hole of the automatic weighing system; according to the weight and the variety that are set by a BOM (bill of material), the crushed rubber particles of various natural rubbers are weighed and conveyed to an internal mixer in a matching manner. Through introduction of the operation of the robot, the labor intensity of workers in a mixing process is reduced, and the quality of personnel allocation is decreased; meanwhile, information in conveying, storing and the like can be collected and controlled by adopting an RFID (radio frequency identification device) technology; huge cost is saved; in addition, through the improvement on the process, the mixing time is shortened, the production efficiency of a rubber compound is improved, and energy consumption is reduced.