This invention provides an application of a Cordyceps militaris extract to suppressing allergy. The Cordyceps militaris extract is an alcoholic extract of fruiting body of Cordyceps militaris and at least contains [beta]-sitostenone. The dosage of the Cordyceps militaris extract is 150mg/kg to 180mg/kg. The extract can suppress the release of [beta]-hexosaminidase, suppress the activation of LAT, block the signal of PI3K, MEKK4, JNK, or c-jun, and reduce generation of mRNA of TNF-[alpha] and IL-4 genes to achieve the efficacy of suppressing allergy. The extract can suppress de novo synthesis and degranulation reactions of allergic lipid mediators and cytokines in mast cells to achieve the efficacy of suppressing allergy reaction.本發明提供一種蛹蟲草(Cordyceps militaris)萃取物用於抑制過敏之用途，所述蛹蟲草萃取物係為蛹蟲草子實體的酒精萃取物；所述該蛹蟲草萃取物至少包含β-扶桑甾醇氧化物(β-sitostenone)；所述蛹蟲草萃取物使用劑量為150mg/kg至800mg/kg；所述萃取物係透過抑制β-己醣胺酶(β-hexosaminidase)之釋放、抑制LAT之活化、阻礙PI3K、MEKK4、JNK或c-jun訊號、降低TNF-α及IL-4基因之mRNA生成以達到抑制過敏之功效；所述萃取物可抑制肥大細胞中之過敏脂質介質與細胞激素的從頭合成及去顆粒化反應以達到抑制過敏反應之功效。
