A therapeutic peptide vaccine consisting of thirteen synthetic long peptides (SLPs), which are 25-35 amino acids in size, derived from the human papillomavirus (HPV) type 16 oncoproteins E6 and E7, with potential immunostimulating and antitumor activities. Upon administration, synthetic long E6/E7 peptides vaccine HPV-01 is taken up and degraded into small pieces by dendritic cells. The processed viral epitopes are presented by dendritic cells, which may stimulate the host immune system to mount both cytotoxic T-cell lymphocyte (CTL) and helper T cell responses against HPV E6/E7-expressing tumor cells. This results in the destruction of tumor cells and leads to decreased tumor growth. The E6 and E7 oncoproteins are implicated in the tumorigenesis in a variety of cancers. The SLPs allow for optimal presentation by antigen-presenting cells.