Objectives : To evaluate the anti-tumor and synergic effect of Bojungikkeehapdaechilki-tang (BJDC) with doxorubicin. Methods : The inhibitory concentration (IC), $IC_{50}{;}and{;}IC_{90}$ of single use of doxorubicin and BIDC with their concomitant treatment against Colon-26 (murine rectum carcinoma) cell line were observed using MTT (microculture tetrazolium test) assay. In addition, their anti-tumor effects were also observed in xenograft nude mice models against Colon-26 cell line. Results : BJDC had only minimal direct anti-tumor effect against Colon-26 cell line but it reduced general depressed signs induced by implantation of the tumor cell lines and increased the total WBC and lymphocyte numbers. Conclusions : It is considered or expected that BJDC extract is reducing the critical toxicity of doxorubicin and has favorable synergic anti-tumor effect when administered conconitently with doxorubicin.