Breast cancer(BC) is a leading cause of cancer-related deaths in women worldwide. There is no effective therapy for patients with metastatic breast cancer. Immunotherapy may be an effective treatment, so, we have designed a complex immunogen derived from the extracellular domain of Human epidermal growth factor receptor2 (HER2/neu) (480–620)and seven tandem repeats of MUC1(VNTR).HER2is recognized as an oncogene involved in abnormal cell growth in BC whichis overexpressed in20–30%of metastatic BC patients where its overexpression results in the loss of cell growth regulationand the development of resistance to apoptosis and MUC1is amucin with overexpressed in90%of BC cases. The chimeric construct(HM)was analyzed using bioinformatics softwares then was synthesized by ShineGene Biotech,Inc.(Shanghai,China)and was cloned in pBI1400 vector under expression promoter of fatty acyle elongase(seed specific promoter)with 2restriction enzymes(RE)of Cfr9I and SacI and then it was introduced to E.coli DH5α strain forreplication. Validity of construct was evaluated by performing PCR with specific primers for both HM gene itself and FAEpromoter and NOS terminator(for checking of whole construct),and digestion with the REs(Cfr9Iand SacI).Then the construct was introduced to Agrobacterium.tumefacience strainLBA4404 and the validity of transformation was evaluated by PCR. Brassica.napus cotyledons were contaminated by transformed A.tumefacience and were selected on selective medium consist of10mg/lit kanamycin as selective agent.Resistant to kan confirms that these plants are transformed.Expression analysis will perform on green plants which have grown on this medium in the future for evaluating of protein expression and antibody analysis will perform on animal model after exposing to this protein.