Objective To compare the effects of truncated therapy and conventional therapy on the lung tissue inflammation of mice with pneumonia induced by influenza virus, so as to explore the mechanism of truncated therapy superior to conventional therapy and its relationship with inflammatory cascade after viral infections. Methods 192 Balb/c mice were randomly divided into healthy group, model group, conventional therapy group and truncated therapy group. Except for the healthy group, the mice of the other three groups were infected with 50 μL 30 LD50 mouse lung-adapted influenza virus strain (FM1) by inoculating intranasally. After 1 h of inoculation, healthy group and model group were administered intragastrically (i.g.) distilled water; conventional therapy group was administered i.g. twice daily Yinqiao Powder for the first three days, then Xijiao Dihuang Decoction for the next four days (totae seven days); truncated therapy group was administered i.g. Xijiaodihuang Decoction twice daily for consecutive seven days. Then the mice were sacrificed by taking the eyeballs on the 2nd, 4th, 6th, and 8th day for sampling and detecting. The WBC count in bronchoalveolar lavage fluid (BALF) was detected, the levels of IL-1β and IL-18 in the supernatants of lung homogenate were measured by ELISA and NOD-like receptor family mem NOD-, LRR-and pyrin domain containing 3 (NLRP3) mRNA in the lung tissue were detected by quantitative realtime-PCR. Results Compared with the model group, the WBC counts of BALF, IL-1β, IL-18 and NLRP3 mRNA in truncated therapy group and conventional therapy group decreased(P<0.01). WBC counts, IL-1β and IL-18 began to show the remarkable differences from that of model group since the 2nd day, while conventional therapy group didn't. On 8th day, WBC count in truncated group was lower significantly than that in the conventional group(P<0.01). On the 4th day of being infected, NLRP3 mRNA of mice lung tissue expressed highly in the model group, while decreased significantly in the truncated group only. Conclusion The truncated therapy which may inhibit the inflammatory reaction induced by innate immunity at the early phase of infection, can prevent the inflammatory cascade, and can truncate the progress of the disease. The potential mechanism is linked to inhibiting the formation of NLRP3 inflammasome, interfering the mature and secretion of IL-1β and IL-18 . [ABSTRACT FROM AUTHOR]