Objective: To investigate the feasibility of the development of aptamer KMF2-1a-based doxorubicin carrier that targets breast cancer cells. Methods: The internalization efficacies of aptamer KMF2-1a and its modified product (drug carrier) into human breast cancer MCF-10AT1 cells were tested by flow cytometry analysis. The incorporation of doxorubicin into the drug carrier was determined by spectrophotometer analysis after their interaction. Results: Flow cytometry analysis showed that both aptamer KMF2-1a and its modified product could be specifically internalized by MCF-10AT1 cells. Spectrophotometer detection demonstrated that doxorubicin was successfully incorporated into the drug carrier. Conclusion: Aptamer KMF2-1a can be internalized specifically by MCF-10AT1 cells, and it can be potentially used as a doxorubicin carrier after modification for targeted breast cancer therapy.