The invention discloses a method for preparing expanded tobacco stem particles and the equipment thereof. The method is characterized in that the method can control the mixed ratio of tobacco stems on the basis of raw material analysis. The method comprises the following steps: mixing materials to obtain tobacco stem containing 10 to 18%of total sugar, 8 to 16% of reduced sugar, 0.3 to 1.5% of nicotine, and 1.0 to 2.0% of total nitrogen, extracting, expanding, storing, regaining moisture, granulating, recovering, shaping, cleaning and air-sorting, flavoring, and balancing to obtain the required expanded tobacco stem particles. The invention eliminates the influences of material difference on the quality of the expanded tobacco stem particles to ensure the stability and the uniformity of the product quality, thus improving the utilization rate of the tobacco stem and further improving the production process of the expanded tobacco stem particles. The method has the advantages of simple, reasonable and easy process flow, stable equipment operation, high efficiency, low energy loss, and good application prospect.