One of the emerging therapeutic strategies for targeted therapy of cancer is the use of chimeric proteins. The p28 peptide has the ability of selective entrance and activating apoptosis in breast cancer cells. The NRC antimicrobial peptide showed cytotoxic activity on various breast cancer cell lines including drug-resistant cells and also on normal cells. Here we designed a chimeric protein consisting of these peptides to determine their targeted effects and to enhance their cytotoxic effects on breast cancer cells. The chimeric protein was cytotoxic to MDA-MB-231 and MCF7 breast cancer cell lines in a dose-dependent manner after 48 h of treatment. In addition, the cytotoxic effects of the p28 alone were significantly lower than the chimeric protein indicating the additive or enhanced effects of the two peptides. Flow cytometry analysis showed that the induced cell death is mediated via apoptosis. The designed chimeric protein had enhanced effects on breast cancer cell lines and exerted its anticancer effects on MCF7 breast cancer cells through mitochondrial caspase dependent and -independent apoptotic pathways. Taken together, the results of this study suggested the chimeric protein to be a reasonable anti-cancer agent which must be further evaluated by subsequent in-vitro and in-vivo preclinical studies.