To investigate the effect of fire preparing method on chemical constituents and clinical effect of Chinese herbal pieces.Methods：Selected 150 cases of patients treated with homologous prescription as study objects，excluding the patients with severe，acute and chronic diseases.Divided them into the observation group and the control group randomly，with 75 cases in each group.The control group was treated with unprocessed Chinese medicine，while the observation group was treated with Chinese herbal pieces processed by fire preparing method.Observed the clinical curative effect.Results：The total effective rate was 81.33%in the control group and 93.33%in the observation group，compared the two groups，difference being significant(P ＜ 0.05)；the incidence of adverse reactions was 12.00%in the control group and 2.66%in the observation group，difference being significant(P ＜ 0.05)；the dissolved amount of carbohydrate，alkaloids，flavonoids and saponins in the observation group was evidently higher than that in the control group，difference being significant(P＜0.05).Conclusion：The application of Chinese herbal pieces processed by fire preparing method has better clinical effect and can reduce adverse reactions and promote the recovery of patients.