In the mouse asthma model, BF significantly reduced hyperresponsiveness, strongly inhibited the increase of total inflammatory cells in BALF induced by OVA, significantly reduced the levels of IL-4, IL-5 and IL-13 in BALF and the specificity of OVA in serum IgE level, reduced inflammatory cell infiltration and goblet cell proliferation, inhibited IκBα degradation of NF-κB, and reduced the level of phosphorylated p65 protein in lung tissue. The gene discussed is IL4; the disease is asthma.