A bivalent cancer vaccine comprised of a modified vaccinia virus Ankara (MVA) strain encoding human mucin 1 (MUC1) and interleukin-2 (IL-2) with potential immunostimulating and antineoplastic activities. Originally developed for the eradication of smallpox, MVA is a highly attenuated and replication-defective strain incapable of virion assembly and exerts potent immunostimulatory activity against antigens. Vaccination with MVA-MUC1-IL2 vaccine may stimulate the host immune system to mount a humoral and cytotoxic T lymphocyte (CTL) responses against tumor cells expressing MUC1, a tumor associated antigen, resulting in tumor cell lysis. Expression of IL-2 augments the specific CTL response against MUC1 expressing cells.