The invention relates to a method for preparing a TiB2 particle-reinforced Al matrix composite through SPS (spark plasma sintering) and belongs to the technical field of preparation of Al matrix composites. The method comprises implementation steps as follows: TiB2 particles and matrix powder are prepared according to designed components; ball-milling activation is performed, and activated mixed powder is obtained; the obtained mixed powder is contained in SPS equipment for SPS and is cooled with the furnace, and the TiB2 particle-reinforced Al matrix composite is obtained. According to the method, the preparation technology is simple, the production cycle is short, the sintering temperature is low, the temperature holding time is short, adverse reactions of reinforcing particles with a matrix can be avoided, the TiB2 particles are controllable in size and content, and the prepared composite is high in compactness and good in performance.