The invention relates to a particulate matter concentration generator and a method of the particulate matter concentration generator, belonging to the technical field of measurement of particulate matter concentration. The generator comprises an axial flow fan, a voltage regulator, particulate matters, a cylinder, a left bottom cylinder, a right bottom cylinder, a left bottom cylinder seat, a right bottom cylinder seat and support posts. When the axial flow fan works, the particulate matters constantly move in a cavity under a wind action and a collision action of the side wall and are dispersed in the cavity to form certain space concentration distribution. The particulate matter concentration generation method comprises the following steps: firstly determining a to-be-generated particulate matter concentration, and then counting the quantity of the particulate matters according to a predetermined relation curve between the particulate matter concentration and the quantity of the particulate matters; secondly, clearing the particulate matters in the particulate matter concentration generator, putting the required quantity of the particulate matters into the particulate matter concentration generator, finally starting the particulate matter concentration generator, and obtaining the required concentration which is generated in a predetermined moment. The particulate matter concentration generator has the advantages of simple structure, convenience in operation and strong practicability.