The development of safe, effective, and affordable vaccines has become a global effort due to its vast impact on overall world health conditions. A brief overview of cancer vaccine characterization techniques, especially in the area of high-resolution mass spectrometry, is presented. It is highly conceivable that the proper use of advanced technologies such mass spectrometry, along with the appropriate chemical and physical property evaluations, will yield tremendous in-depth scientific understanding for the characterization of vaccines in various stages of the development. This work presents the physiochemical and biological characterization of two cancer vaccines: Racotumomab and Her1-ECD. Racotumomab monoclonal antibody is a murine anti-idiotypic antibody that mimics N-glycolyl-GM3 gangliosides. This antibody has been tested as an anti-idiotypic cancer vaccine, adjuvated in Al(OH)3, in several clinical trials for melanoma, breast, and lung cancer. The Her1-ECD is a vaccine preparation based on the extracellular domain of HER1 and it is being evaluated in Phase I clinical study in patients with refractory prostate cancer.