OBJECTIVE: To observe the effect of "Yang-warming and kidney essence-replenishing" herbal paste on cold-related asthma exacerbation. METHODS: One hundred and fifty one patients with moderate to severe persistent asthma were randomly divided into a treatment group (n=74) and a control group (n=69). Both groups were given basic treatment according to the Global Initiative for Asthma scheme. The treatment group was also treated with herbal paste in the winter. The frequency of asthma exacerbation, cold and cold-re-lated asthma exacerbation, scores of the asthma control test (ACT), and kidney-deficiency syndrome during the one-year follow-up in each group were recorded. RESULTS: Compared with the control group, the onset frequencies of catching cold, asthma exacerbation, cold-related asthma exacerbation, and kidney-deficiency syndrome score were significantly reduced. There was no significant difference in scores of ACT between the two groups. CONCLUSION: "Yang-warming and kidney essence-replenishing" herbal paste could reduce cold-related asthma exacerbation.