OBJECTIVE: To explore the acting mechanism of acupuncture treatment for dispersing Fei, invigorating Pi and reinforcing Shen (DFIPRS) on bronchial asthma. METHODS: Seventy-one chronic asthma patients in persistent or remission period were randomly assigned to two groups with stratified method, the treated group (40 cases) and the control group (31 cases). Anti-asthmatic medicine were given to both groups and acupuncture therapy to the treated group additionally on the acupoints for DFIPRS including Quchi (Lt11), Lieque (LU7), Yuji (Lu10), Neiguan (P6), Zusanli (ST36), Sanyinjiao (Sp6) and Taixi (K13) using uniform reinforcing-reducing manipulation. The changes of heart rate variability (HRV) frequency-domain index and the pulmonary function were observed before and after treatment, and the immediate effect before and after the first needling of acupuncture was also observed in 17 patients. RESULTS: After acupuncture treatment, the indices of pulmonary function improved significantly and the function of vegetative nervous system, showed by HRV, were also elevated in the treated group (P < 0.05 or P < 0.01) and significantly superior to that in the control group after treatment (P < 0.05 or P < 0.01 ). CONCLUSION: Acupuncture therapy could significantly improve pulmonary function of asthma patients, its mechanism may be related to the regulation of vegetative nerve function.