MUC1 is a high-molecular-weight glycoprotein that is overexpressed in adenocarcinomas and hematological cancers. Numerous preclinical studies in mice have demonstrated that MUC1 is immunogenic, and that cellular and humoral immune responses could be induced depending on the MUC1 vaccine formulation. MUC1-based vaccines have quickly entered into human clinical trials, and immune responses and some clinical responses have been reported. Here, we give an up-to-date review of some of the MUC1-based vaccines that have entered clinical trials and their results in cancer patients.