Laser Immunotherapy is a recently-developed treatment for metastatic cancers that synergistically applies photothermal laser irradiation in conjunction with a local immunoadjuvant to induce a host anti-cancer immune response. We have used laser immunotherapy to treat orthotopic pancreatic tumors in mice. In this study, we used magnetic resonance imaging to guide laser immunotherapy for interstitial treatment of metastatic pancreatic tumors in mice. Furthermore, we used MRI to investigate tumor location, guide laser treatment, and monitor the photothermal effects using proton resonance frequency shift thermometry. Our results indicate that laser immunotherapy could be an effective modality for late-stage pancreatic cancer patients, and that MRI thermometry can effectively monitor treatment for guidance.