The invention discloses a chewable tablet for preventing and treating oral ulcers and a preparation method thereof. The chewable tablet of the present invention includes the following raw materials: Bupleurum radix, Anemarrhena anemarrhena, Rhizoma rhubarb, Golden fruit olive, Baiyun flower root, Lu honeycomb, Fritillaria, Bergamot tablets, Predict, Shi Jianchuan, Hedyotis diffusa, Fisheye Grass, heather leaves, L-arabinose, gum base, stabilizer, pigment, gloss agent; all medicines in the chewable tablet of the present invention are combined, synergistically Synergize, play the effect of nourishing yin and clearing away heat, invigorating spleen and replenishing qi, detoxifying and astringent, suitable for various types of oral ulcers; compared with the prior art, the present invention integrates anti-bacteria, anti-virus, anti-infection, and improves immune function. Heavy action in one body, high efficiency.