Objective:To investigate the efeect-enchancing and toxicity-reducing action of the extract of Ban Zhi Lian (半枝莲Herba Scutellariae Barbatae,EHSB)for chemotherapy in hepatoma H22 tumor-bearing mice.Methods:The tumor-bearing mice were divided into 6 groups randomly:a model group.a high dose EHSB group,a low dose EHSB group,a 5-fluorouracil(5-FU)group,a 5-FU+high dose EHSB group and a 5-FU+low dose EHSB group.and with a normal group set as the controls.All the groups were treated for 10 days.The life prolongation rate,toxic reactions of chemotherapy,WBC count,the body weight,tumor weight,thymus index and spleen index.and phagocytic function of intra-abdominal macrophages were investigated in the H22 tumor-bearing mice.Resuits:The increase of the body weight in both the 5-FU+EHSB groups was significantly higher than that in the 5-FU group,with the toxic reactions such as anorexia,abdominal distension and emaciation significantly alleviated.Growth of the tumor was significantly inhibited in the high dose EHSB group,the 5-FU group,the 5-FU+high dose EHSB group,and the 5-FU+low dose EHSB group.The survival time in the 5-FU+high dose EHSB group and the 5-FU+low dose EHSB group was significantly prolonged as compared with that of the 5-FU group.The life prolongation rate was 98.72%in the 5-FU+high dose EHSB group and 52.11%in the 5-FU+low dose EHSB group.Growth of the transplanted tumor was significantly inhibited in the high dose EHSB group,the 5-FU group,the 5-FU+high dose EHSB group,the 5-FU+low dose EHSB group.The tumor inhibition rate in the high dose EHSB group,the 5-FU group,the 5-FU+high dose EHSB group and the 5-FU+low dose EHSB group was 36.98%,42.26%,65.28% and 52.45%.respectively.5-FU combined with a high-dose EHSB could significantly enhance the tumor inhibition rate (P＜0.05).The thymus index and the spleen index significantly increased in the high dose EHSB group,and atrophy of the immunological organs induced by chemotherapy was improved in the 5-FU+high dose EHSB group and in the 5-FU+low dose EHSB group.The WBC count decreased significantly in the 5-FU group,but increased in both the 5-FU+EHSB groups.The phagocytic function of intra-abdominal macrophages was increased in both the 5-FU+EHSB groups.with the phagocytic rate and the phagocytic index increased bv 78.55%and 81.63%in the 5-FU+high dose EHSB group and by 43.97% and 44.90%in the 5-FU+low dose EHSB group.Conclusions:EHSB can significantly enhance the tumor inhibition rate of 5-FU,reduce the toxic effects,prolong the survival time,and improve immune function in the H22 tumor-bearing mice.