Abstract: Objective To evaluate the preventive effectiveness of modified Yupingfeng powder decoction (astragalus root,atractylis ovata,radix sileris,the root bark of white mulberry,liquoric root,etc.were included) smearing on cracked nipple and pain during breastfeeding in in Chinese breastfeeding women. Methods Using the randomized control design,279 primipara in our hospital between December,2014 and June,2015 were enrolled and randomized into control group,pre and postnatal intervention group and postnatal intervention group.Women in pre and postnatal intervention group were treated with modified Yupingfeng powder decoction twice a day on the morning and night started from 37 gestation weeks till 7 days postpartum,while the postnatal intervention group were started from 2 hours after delivery till 7 days postpartum,and the control group were treated with plain water or colostrums if it was available.Breastfeeding skills were implemented under the supervision of midwives.Nipple trauma and pain intensity were evaluated by nipple trauma score and visual analog scale (VAS) every day after 12 hours postpartum.Baby feeding condition was followed up by phone calls 6 months after delivery. Results The incidence of cracked nipple were 10.53%,21.28% and 25.56% in the pre and postnatal intervention group and control group,respectively,with significant difference (P<0.05).There was no significant difference among the three groups in severity.There were 17 cases (17.89%) in pre and postnatal intervention group,30 cases (31.91%) in postpartum intervention group and 35 cases (38.89%) in control group suffered from severe nipple pain,and the difference among the three groups was significant (P<0.05). Conclusion The use of modified Yupingfeng powder decoction from 37 gestation weeks to 7 days postpartum is effective on preventing nipple cracks and relieving nipple pain in Chinese Breastfeeding Women.The treatment may indirectly increase the rate of pure breastfeeding in 6 months.