The invention belongs to the field of traditional Chinese medicines, and provides traditional Chinese medicine powder for treating infantile diarrhea and a preparation method thereof. The traditional Chinese medicine powder is prepared from the following raw medicinal materials: codonopsis pilosula, medicated leaven, radix aucklandiae, bombyx batryticatus, hawthorn, white pepper, dried ginger, rhizoma atractylodis, illicium verum and scutellaria baicalensis. The traditional Chinese medicine powder is simple in using method, cannot cause pain, need not oral administration, does not irritate intestines and stomach, and does not have toxic or side effect; the response is quick, and a child with infantile diarrhea can be cured generally in 3-4 days; the effective rate is high, and the total effective rate is 100 percent; all raw materials are not extremely lacked, and are easily available; and the preparation method is simple and feasible, only comprises the steps of grinding and mixing.