Abstract: Higher somatic cells in milk is the main indicator of nonclinical mastitis for cows. Based on the traditional theory of Chinese medicine, a Chinese herbal medicine pharmaceutical ＂droping somatic cells Chinese medicine powder＂ was prepared, and it has some functions of clearing and detoxifying, expediting channel and activating meridian, enhancing mammary＇s resistance and immune. A clinical test on cows＇ nonclinical mastitis for the Chinese medicine powder was carried out. Results show that effective rate of the Chinese medicine powder to decrease somatic cells in cows＇ nonclinical mastitis eases after one course of treatment （7 days） was 83%, slightly higher than control （80%）. Because the Chinese medicine powder is a pure herbal formula, so it can be used as a substitute product of some prohibited drugs with commercially available effect which are forbid to use at the period of lactation in cows.